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SCERT AP 7th Class Maths Solutions Pdf Chapter 10 Construction of Triangles Unit Exercise Questions and Answers.

AP State Syllabus 7th Class Maths Solutions 10th Lesson Construction of Triangles Unit Exercise

Construct triangles for the following :

Question 1.
Construct ∆PQR with measurements PQ = 5.8 cm, QR = 6.5 cm and PR = 4.5 cm.
Answer:
Given measurements of ∆PQR are PQ = 5.8 cm, QR = 6.5 cm and PR = 4.5 cm

Steps of Construction:

1. Draw a rough sketch of triangle arid label it with given measurements.
2. Draw a line segment with PQ = 5.8 cm.,
3. Draw ati arc with centre P and radius 4.5 cm.
4. Draw another arc with centre Q and radius 6.5 cm. to intersect the previous arc at R.
5. Join PR and QR.
   Thus, required ∆PQR is constructed with the given measurements.

Question 2.
Construct an isosceles triangle LMN with measurements LM = LN = 6.5 cm and MN=8cm.
Answer:
Given measurements of ∆LMN are LM = LN = 6.5 cm and MN = 8 cm.

Steps of Construction :

1. Draw a rough sketch of triangle and label it with given measurements.
2. Draw a line segment with MN = 8 cm.
3. Draw an arc with centre M and radius 6.5 cm.
4. Draw another arc with centre N and same radius (6.5 cm) to intersect the previous are at L
5. Join ML and NL.
   Hence, required ∆LMN is constructed with the given measurements.

Question 3.
Construct ∆ABC with measurements ∠A = 60°, ∠B = 706 and AB = 7 cm.
Answer:
Given measurements of ∆ABC are ∠A = 60°, ∠B = 70° and AB = 7 cm.

Steps of Construction :

1. Draw a rough sketch of triangle and label it with given measurements.
2. Draw a line segment AB = 7 cm.
3. Draw a ray AX such that ∠BAX = 60°.
4. Draw another ray BY such that ∠ABY = 70°.
5. Name the intersecting point of AX and BY as C.
   Hence, required ∆ABC is constructed with the given measurements.

Question 4.
Construct a right angled triangle XYZ in which ∠Y = 90°, XY = 5 cm and YZ = 7 cm.
Answer:
Given measurements of ∆XYZ are ∠Y = 90°, XY = 5 cm and YZ = 7 Cm.

Steps of Construction:

1. Draw a rough sketch of triangle and label it with given measurements.
2. Draw a line segment with XY = 5 cm.
3. Draw a ray YP such that ∠XYP = 90°
4. Draw an arc with centre Y and radius 7 cm to intersect YP at point Z.
5. Join XZ.
   Hence, required ∆XYZ is constructed with the given measurements.

Question 5.
Construct an equilateral triangle DEF in which DE = EF = FD = 5 cm.
Answer:
Given measurements of ∆DEF are DE = EF = FD = 5 cm.

Steps of Construction:

1. Draw a rough sketch of the triangle and label it with the given measurements.
2. Draw a line segment DE of length 5 cm.
3. Draw an arc with centre D and radius 5 cm.
4. Draw another arc with centre E and the same radius (5 cm) to intersect the previous arc at F.
5. Join DF and EF.
   Thus, the required triangle ∆DEF is constructed with the given measurements.

Question 6.
Construct a triangle with a non-included angle for the sides of ST and SU of lengths 6 v and 7 cm. respectively and ∠T = 80°.
Answer:
Given measurements of ∆STU are ST = 6 cm, SU = 7 cm and ∠T = 80°.

Steps of Construction:

1. Draw a rough sketch of triangle and label it with given measurements.
2. Draw a line segment with ST = 6 cm.
3. Draw a ray TX such that ∠STX = 80°.
4. Draw an arc with centre S and radius 7 cm to intersect TX at point U.
5. Join SU. Hence, the required triangle ∆STU is constructed with the given measurements.

Question 7.
Can you construct ∆DEF with DE = 7 cm, EF = 14 cm and FD = 5 cm. ? If not give reasons. .
Answer:
No, we can’t construct the triangle. Because the given sides of ∆DEF are DE = 7 cm, EF = 14 cm, FD = 5 cm.
In any triangle sum of any. two sides are always greater than the third side.
DE + FD = 7 + 5 = 12 cm < 14 cm
Sum of DE + FD < EF.
So, with the given measurements construction of ADEF is not possible.

SCERT AP 7th Class Science Study Material Pdf 9th Lesson Heat, Temperature and Climate Textbook Questions and Answers.

AP State Syllabus 7th Class Science 9th Lesson Questions and Answers Heat, Temperature and Climate

7th Class Science 9th Lesson Heat, Temperature and Climate Textbook Questions and Answers

Improve Your Learning

I. Fill in the blanks.

1. Doctor uses ______ thermometer to measure the human body temperature.
2. The best liquid for a thermometer is _____
3. The force applied by air on any surface in contact is called ______
4. The average weather pattern taken over a long time is called the _____ of the place
5. The amount of water vapour present in the air is called _____
Answer:
1. clinical
2. mercury
3. air pressure
4. climate
5. humidity

II. Choose the correct answer.

1. A student observe day-to-day conditions of the atmosphere on three consecutive days and recorded his observations. She wants to show the data using a graph. Which graph is suitable for her?
a) climate graph
b) weather graph
c) temperature
d) humidity graph
Answer:
b) weather graph

2. Conduction of heat takes place in
a) metals
b) liquids
c) gases
d) air
Answer:
a) metals

3. Average human body temperature is
a) 0°C
b) 20°C
c) 37°C
d) 100°C
Answer:
c) 37°C

4. Number of divisions in Fahrenheit scale
a) 180
b) 100
c) 50
d) 200
Answer:
a) 180

III. Matching.

Answer:

IV. Answer the following questions.

Questions 1.
What are similarities and differences between the laboratory thermometer and the clinical thermometer?
Answer:

Question 2.
Draw the diagram of a clinical thermometer and label its parts.
Answer:

Question 3.
Give two examples for conductors and insulators each.
Answer:
Example for conductors:
Aluminum, iron and copper etc.

Example for insulators:
Water, air, clothes, glass, cork, plastic, wood etc.

Question 4.
Buchhanna thinks that the concepts • weather and climate are the same. Do you agree with him? Justify your answer.
Answer:
I do not agree the Buchhanna’s statement.

1. The day-to-day variations in the components like temperature, humidity, rainfall, wind speed are called weather. But, the average weather pattern taken over a long period, say 25 years or more is called the climate of the place.
2. Weather keeps on changing and changes are very fast too. But, climate of a place remains unchanged for a long period Of time.
3. Rapid changes occur in weather. But no rapid changes occur in climate.
4. Weather affects our daily life. But climate affects our lifestyle.
5. Weather gives the information about atmospheric conditions in a specific area and time. But, climate gives for a long time of period.

Hence, weather and climate are not the same.

Question 5.
Prepare two questions for a questionnaire for “farmers on climate change”.
Answer:
a) What type of climate changes do you observe in last ten years?
b) What changes have been made in the cultivation of crops due to climate changes?

Question 6.
Give two precautions to be taken while using a clinical thermometer?
Answer:

1. Wash the thermometer with water or an antiseptic solution before and after use.
2. Before use, the level of mercury should be less than 35°C, otherwise shake it.
3. Don’t touch the bulb while taking reading.
4. Handle the thermometer carefully, because it is a glass ware.
5. Take the reading after increasing of the mercury level is stopped.

Question 7.
Define conduction. Explain the process of transfer of heat by conduction with your own examples.
Answer:
1) The process of transfer of heat from hotter to colder end through the conductor is called conduction. This mode of transfer of heat happens more in solid conductors.

2) Example 1:
It takes some time for the heat to reach the end of the spatula placed in the cooking vessel. The heat from cooking vessel transfers to the end of the spatula gradually. This type of heat transfer is called conduction.

3) Example 2:
The edges of the steel plate with burning coal burn our hand while holding it. Here the heat transfers from the middle of the plate to the edges gradually.

4) Example 3:
If we put a needle by holding it in the candle flame, it causes burn to our hand. It is due to conduction of heat.

Question 8.
What are the measuring components of weather and explain about them?
Answer:
Maximum and minimum temperature of a day, air pressure, rainfall, wind speed and humidity are called measuring components of weather.

1) Maximum and minimum temperature of a day:
Maximum and minimum tempera-ture of a day are the highest and lowest temperature recorded respectively during a day. Six’s maximum and minimum thermometer is one of the meteorological in-struments used to measure maximum (highest) and minimum (lowest) temperatures of a place in a day.

2) Air pressure:
The force applied by air on any surface in contact is called “air pres-sure”. Air pressure is measured in height of mercury level in centimeters and it is measured with a barometer.

3) Rainfall:
The amount of water falling in rajn within a given time and area is called Rain fall. Rainfall is measured in millimeters by using a rain gauge.

4) Wind speed:
Wind move is caused by difference in the air pressure in two places. The speed of wind can be measured using a device called an anemometer.

5) Humidity:
The water vapour present in the air is called humidity Hygrometer is used to measure humidity in air and it is expressed in grams per cubic meter.

Question 9.
Explain an activity to show that “air experts pressure”?
Answer:

1. Take an empty bottle and a balloon.
2. Insert the balloon into the bottle.
3. Stretch the balloons over the opening of the bottle as shown in the figure.
4. Now try to blow air into the balloon inside the bottle.
5. But it is not easy to blow air when it is inside the bottle.
6. There is some force inside the bottle stopping you to do so.
7. This is because the force applied by the air inside the bottle.
8. The force applied by air on any surface in contact is called “air pressure”.

Question 10.
Explain the construction and working of six’s maximum and minimum thermometer?
Answer:

1. Six’s maximum and minimum thermometer is one of the Meteorological instruments used to measure maximum (highest) and minimum (lowest) temperatures of a place in a day.
2. James Six invented this thermometer in 1780.
3. It has a cylindrical ‘Bulb A’, and ‘Bulb B’ connected through a ‘U-shaped tube’ con-taining mercury.
4. Bulb A contains alcohol, and bulb B c’ontains alcohol and its vapours.
5. When the temperature increases, the alcohol in the bulb A expands and pushes the mercury in the U tube, this makes indicator N to move up.
6. This indicates the maximum temperature of the day.
7. When the temperature decreases, alcohol in the bulb A contracts and pulls the mercury back. This makes indicator M to move up.
   
8. This indicates the minimum temperature of the day.
9. After taking readings the indicators M and N are brought to their original places by using a magnet.

7th Class Science 9th Lesson Heat, Temperature and Climate InText Questions and Answers

7th Class Science Textbook Page No. 35

Question 1.
Mention the terms used in the conversation?
Answer:
Heat, cold, weather, temperature, minimum temperature.

Question 2.
What is the difference between Heat and Temperature?
Answer:
Heat flows from a body of high temperature to a body of low temperature . The degree of hotness or coldness is called temperature.

Question 3.
What is meant by climate of a place?
Answer:
The average weather pattern taken over a long period, say 25 years or more, is called the climate of a place.

Question 4.
Which form of energy help us to cook rice?
Answer:
Heat energy.

Question 5.
Which energy turns the water into vapour, while boiling?.
Answer:
Heat energy.

Question 6.
Why do you feel the heat when you hold a cup of warm milk to drink?
Answer:
We feel hot when heat energy flows from milk to our body. Here we gain heat energy from milk.

Question 7.
Why do you feel cool when you drink a glass of lassi?
Answer:
We feel cool, when heat energy flows from our body to lassi. Here, we lose heat energy.

7th Class Science Textbook Page No. 36

Question 8.
What determines the direction of heat flow?
Answer:
Heat flows from a body of higher temperature to a body of lower temperature. This direction is determined by temperature.

Question 9.
Have you heard about temperature, when you suffer from fever?
Answer:
Yes, I have.

Question 10.
What is temperature?
Answer:
The degree of hotness or coldness is called temperature.

Question 11.
What are the differences between heat and temperature?
Answer:

7th Class Science Textbook Page No. 37

Question 12.
Why are cooking utensils made of metals while their handles are made of plastic or wood?
Answer:

1. Some materials allow heat through them, this property is called conductivity.
2. We use metals to make cooking vessels because they allow heat through them.
3. We use material which do not allow heat to pass through as handles.
4. So, cooking utensils made of metals while their handles are made of plastic or wood.

7th Class Science Textbook Page No. 38

Question 13.
How does conductors transfer heat energy through them?
Answer:
Heat is transferred in the conductors from one end to another end by the mode of conduction.

Question 14.
How does water transfer heat energy from one place to another?
Answer:
Water transfers heat energy in the mode of convection.

Question 15.
How is heat energy transferred from the Sun to the Earth?
Answer:
Heat energy transferred from the Sun to the Earth in the mode of radiation.

Question 16.
Many times, Karthik observed that the handle of the spoon becomes hot when it is left for some time in hot oil, hot curry, hot tea or hot milk. Can you guess why does it happen? What is this process called?
Answer:
This is because heat is transferred from one end to another end by the mode of conduction.

7th Class Science Textbook Page No. 39

Question 17.
We know, water is a poor conductor of heat. But, when we heat water on a stove to take a bath, how does the surface of the water get heated?
Answer:
This happens due to the transfer of heat by a mode called convection.

7th Class Science Textbook Page No. 40

Question 18.
What happens if there is no medium (solid, liquid, gaseous substances) to transfer heat between two objects or two places?
Answer:
Heat transfers in the form of waves from one place to another, if there is no medium like solid, liquid, gas.

Question 19.
Recollect the conversation between the three friends Rafi, John, and Satyanarayana at the fire place and can you guess how does the heat energy transfer from the fire place to their bodies?
Answer:
This is because of heat transfer in the form of waves from one place to another.

Question 20.
How does a thermal scanner work, without being in contact with the human body?
Answer:
The thermal scanner receives the heat in the form of radiation to measure our body temperature.

Question 21.
Which instrument can control the transfer of heat (loss of heat)?
Answer:
Thermos flask can control the transfer of heat (loss of heat) and retain hotness of tea for a few hours.

Question 22.
How can we use Thermos flask to stop all modes of heat transfer?
(OR)
Do you know how Thermos flask works?
Answer:

1. Thermos flask has a two layered glass container and the air between these layers is removed to create a vacuum.
2. The inner silver coating protects the contents (tea, coffee, milk) poured in the flask from losing heat through radiation.
3. As there is no medium between the walls of the flask. Neither conduction nor con-vection of heat takes place.
4. As a result, heat is not transferred outside the flask so it is retained inside the flask for a few hours.

7th Class Science Textbook Page No. 41

Question 23.
Is it possible to keep the hotness of tea in flask forever?
Answer:
No, gradually a little amount of heat is lost from the lid by convection currents and a small amount of heat by conduction through the glass. Therefore, the tea does not retain heat for a long time or forever.

Question 24.
What changes can we observe in the size of material when it transfers heat energy?
Answer:
We can observe enlarging in the size of material when it transfers heat energy. This is due to increase in the energy of particles present in the substance.

Question 25.
Why are small gaps left between rails in railway tracks?
Answer:

1. Particles of substances occupy more space when they get heated.
2. In the hot days rails of the railway tracks enlarge (expand) due to heat energy.
3. It causes damage to the rails.
4. So, small gaps are left between rails in railway tracks.

Question 26.
What change occurs to the level of mercury in thermometer when it is kept in the mouth of a person suffering from fever?
Answer:
The level of mercury in thermometer increases when it is kept in the mouth of a person suffering from fever. This is due to expansion of mercury on heating.

Question 27.
Why does puri swell when it is put in hot oil?
Answer:
Puri swells when it is put in hot oil, because water in the substance is expanded in the hot oil.

Question 28.
What happens when you heat a piece of metal?
Answer:
When you heat a piece of metal it expands on heating.

Question 29.
Is there any change in the shape and size of a metal?
Answer:
Yes, shape and size changes in the expansion on heating a metal.

7th Class Science Textbook Page No. 42

Question 30.
Do the liquids also expand on heating as solids?
Answer:
Yes

Question 31.
Do gases also expand on heating like solids and liquids?
Answer:
Yes

Question 32.
What happens when air is heated?
Answer:
Gases (Air) expands on heating and occupies more space.

7th Class Science Textbook Page No. 43

Question 33.
How can we use expansion of liquids?
Answer:
We can make devices like thermometers by using the property of expansion of liquids on heating.

Question 34.
What device we use to measure the temperature of a substance and how it works?
Answer:
Thermometers are used to measure temperature, this works on the expansion of liquids (mercury).

Thermometer – roleplay (personification)

Question 35.
How are you?
Answer:
I am fine.

Question 36.
Do you know me?
Answer:
Yes, I know you. You are a thermometer.

Question 37.
Have you ever seen me?
Answer:
Yes, I have seen in my home and hospital.

Question 38.
Try to recall how I look like?
Answer:
You are made of a narrow glass tube with thick walls which is closed at one end and You have a bulb of mercury or alcohol on the other end.

Question 39.
Do you know why mercury or alcohol is used in me?
Answer:
Mercury and alcohol have the best properties to measure temperature.

7th Class Science Textbook Page No. 44

Question 40.
Do you ever observe any marks on Alcohol thermometer? Can you guess what are they?
Answer:
Yes, I observed. Those marks are called scales.

7th Class Science Textbook Page No. 45

Question 41.
How can we use laboratory and clinical thermometers?
Answer:
Using of a laboratory thermometer:

1. Place the mercury bulb of the thermometer in a liquid, so that the bulb immerses in it.
2. Wait for some time till the mercury level shows a constant reading.
3. And take the reading at the level of the mercury.

Using of a clinical thermometer:

1. Wash the clinical thermometer properly with an antiseptic solution.
2. To lower the mercury level, hold the thermometer firmly and give some jerks.
3. Ensure that it falls below 35 °C.
4. Now place the bulb of the thermometer under your friend’s tongue.
5. After one or two minutes, take the thermometer out and note the reading.
6. This is your body temperature.
7. Don’t hold the thermometer by the bulb while reading it.

7th Class Science Textbook Page No. 46

Question 42.
What is your friend’s body temperature?
Answer:
98.4°F. (write your friend’s body temperature)

Question 43.
Why are armpit or part below tongue selected to record temperature?
Answer:
The clinical thermometer is used to determine the temperature of the interior of the body. The part under the tongue is the most accessible area to get accurate interior temperature. So, temperature is taken underneath the tongue. But it is difficult and inconvenient for kids to hold the thermometer under their tongue. So armpit will be used for kids to take body temperature, even though it is not accurate.

Question 44.
Can you tell why smoke always rises up?
Answer:
Smoke and hot air moves up because it expands and becomes lighter.

Question 45.
Why do we have ventilators and exhaust fans on the upper parts of the wall?
Answer:
Smoke and hot air moves up because it expands and becomes lighter. That’s why we have ventilators and exhaust fans on the upper parts of the wall to exhaust hot air and smoke from a room.

Question 46.
What happens at a place, where air expands and rises up?
Answer:
When air expands and rises up it creates a low pressure area.

Question 47.
Who occupies that place which is vacated by hot air?
Answer:
The air high pressure from surrounding to move and occupy that place.

Question 48.
What makes the cooler air come into that place?
Answer:
Low air pressure.

7th Class Science Textbook Page No. 47

Question 49.
Have you ever seen high speed winds blowing over the roofs of houses?
Answer:
Yes.

Question 50.
Is there any relation between these components and the weather of a place?
Answer:
The measurements of components like wind speed, rainfall, temperature etc. in a certain-time and location is called weather.

Question 51.
Do we have any other components of this kind?
Answer:
Yes, humidity is the other components of this kind.

7th Class Science Textbook Page No. 48

Question 52.
Where does this evaporated water go?
Answer:
All the evaporated water from different water bodies go into air.

Question 53.
Do you know what we call this evaporated water present in air ?
Answer:
This water vapour present in the air is called humidity.

Question 54.
What is the role of humidity in sunstroke?
Answer:

1. Evaporation of sweat from our body makes us cool to maintain our body temperature.
2. In summer, the humidity of air is high.
3. Due to high humidity and temperature, it becomes difficult to evaporate the sweat from our body to cool it down.
4. But still our body losses water.
5. High temperatures, along with humidity sometimes may cause heat stroke or sunstroke.

7th Class Science Textbook Page No. 49

Question 55.
Do all the days have the same values of components of weather?
Answer:
No. All are not the same on all days. This causes variations in atmospheric conditions.

Question 56.
How can we get information of weather at a place?
Answer:
We can get details of weather from weather reports and you can see these symbols on television, newspapers and in weather forecasting.

Question 57.
Have you ever seen the symbols shown in the figure?
Answer:
Yes, I saw it in TV and newspapers.

7th Class Science Textbook Page No. 50

Question 58.
How can we present these components of weather, more effectively?
Answer:
We present these components of weather; more effectively by tabulating these values and by drawing these graph.

Question 59.
Do the climate of a place changes like weather?
Answer:
The climate of a place does not change like weather. Climate of a place remains unchanged for a long period of time.

Question 60.
What are the measuring components of climate?
Answer:
Temperature, air pressure, rainfall, wind speed and humidity are the measuring components of climate.

Question 61.
Is weather and climate are one and the same?
Answer:
Not the same.

7th Class Science Textbook Page No. 51

Question 62.
What happens if the components of climate changes abnormally?
Answer:
The abnormal variation in the components of climate is called climate change. These variations may affect all parts of the world.

Think & Respond

7th Class Science Textbook Page No. 38

Question 1.
When two ice cubes are placed on wood and aluminium objects with same size which ice cube will melt faster, why?
Answer:

1. The ice cube placed on the aluminium object will melt faster.
2. Because of aluminium is a good conductor of heat.
3. Transfer of heat takes place quickly.
4. But wood is a poor conductor of heat and transfer of heat takes place slowly.

Question 2.
Why do animals that live in colder regions have more fur and thick fat layer under the skin?
Answer:

1. Animals that live in colder areas have to protect their bodies against extremely cold environmental conditions.
2. Their bodies cannot withstand such cold climates.
3. So, they have thick white fur on their body.
4. This provides an additional layer over their skin.
5. Thick white fur acts as insulator of heat and stops the heat transfer from body to outside and vice versa.
6. Animals in colder regions have thick layers of fat, because fat acts as an insulator and doesn’t let their body heat escape, which helps them survive in such extreme temperatures.

Question 3.
Why do we wear woolen clothes in winter?
Answer:
As wool is a very good insulator and a poor conductor of heat, woolen clothes keep the body warm and protect it from the cold winds.

Question 4.
Why do most of the desert animals live in burrows (inside soil)?
Answer:
Reptiles, insects and most of the desert animals live in burrows below the surface of the soil or sand to escape the high temperatures at the desert surface.

7th Class Science Textbook Page. No. 39

Question 5.
Why are the Upper layers of water in a pond or a lake hotter than the lower layers during the hot summer?
Answer:

1. The heat from the sun is reached to the Upper layers of the lakes first.
2. We know that heat transfers in convectional mode in water. .
3. Convectional currents take more time to reach the lower layers as there are in deep.
4. This means it takes more time to transfer of heat to the bottom of the lake or pond.
5. The water of the surface layer is evaporated by absorbing heat and does not heat up quickly.
6. As a result heat does not reach the lower layers of the lake. It is another reason.

7th Class Science Textbook Page No. 41

Question 6.
Why the electric power lines (wires) are held loose on poles?
Answer:

1. Wire is made up of metal. So, it expands on heating and contracts on cooling.
2. If the wire is fixed tightly with maximum tension between two poles, may cut due to contraction on cooling conditions in winter,
3. So, the electric power lines (wires) are held loose on poles to minimize the tension in the wires.

Question 7.
Why are rollers kept under the beams of metal bridges?
Answer:

1. Roller supports are commonly located at one end of long bridges.
2. This allows the bridge structure to expand and contract with temperature changes and prevents damage.

DO THIS (Page No. 49)

Collect the information about symbols of the weather report and display them in
the classroom.
Answer:

Activities and Projects

Question 1.
Prepare a report by collecting different types of materials in your surroundings and classify them into good and poor conductors based on their conductivity.
Answer:

Question 2.
Visit a veterinary doctor and find out the normal body temperature of domestic animals and birds.
Answer:

Question 3.
Visit the nearby Tahsildar office or meteorological department office and observe different instruments which are used to measure components and record your ob-servations.
Answer:

Question 4.
Measure the body temperature of atleast 10 of your Mends and prepare a report.
Answer:

Question 5.
Note down maximum and minimum temperature of five consecutive days from today by using 6 minimum and maximum thermometer.
Answer:

Activities

Activity – 1

Question 1.
How do you prove that heat is a form of energy?
(OR)
Write an activity to explain the heat concept.
Answer:

1. Take a glass bottle and a one-rupee coin.
2. Wet the mouth of the bottle and place a coin on it.
3. Rub your hands together to produce heat.
4. Now place them around the bottle.
5. Observe the coin. It moves.
6. Reason:- the movement in the coin is caused by heat supplied to the bottle from your hands.
7. Conclusion:-So, we can say heat is a form of energy.

Activity – 2

Question 2.
How do you show the degree of hotness or coldness through an activity?
(OR)
write an activity to understand the concept of temperature.
Answer:

1. Take some Iuke-warm water in one glass and hot water (which you can bear) in another glass.
2. Touch them and feel the hotness of both.
3. Take a glass of cool water and cubes of ice in another glass.
   
4. Touch them feel the coldness of both.
5. You will feel hot water is hotter than Luke warm water and ice is cooler than cool water.
6. The variations of hotness, coldness can be termed as degree of hotness and coldness.
7. The degrees of hotness or coldness is called “Temperature”.

Activity – 3

Question 3.
Write an activity to understand the thermal conductivity.
(OR)
Write an activity to prove that the good conductors allow the heat to pass through them and insulators do not.
Answer:

1. Take a glass beaker and pour some hot water in it. mmmd
2. Now dip a metal spoon, plastic spoon, wooden stick, glass rod, and long iron nail into it as shown in the figure.
3. Wait for few minutes and touch each and every object.
4. Fill in the table given below.

From this activity, you will know that good conductors allow the heat to pass through them and insulators do not.

Activity – 4

Question 4.
Write an activity to show that heat is transferred from one end to another end by the mode of conduction.
(OR)
Write an activity to show the conduction in metals.
Answer:

1. Take a metal spoon and fix four pins with candle wax on it at equal distances from each other.
2. Now place one end of this spoon with pins in a flame of candle holding the other end of it with a piece of cloth.
3. Observe for a while. Record your observations.
4. You will observe the dropping of pins one after another from the flame end of the spoon.
5. This is due to the transfer of heat from the end kept in the flame (hotter end) towards your hand (colder end) through a spoon (metal).
6. This process of transfer of heat from hotter to colder end through the conductor is called conduction. This mode of transfer of heat happens more in solid conductors.

Activity – 5

Question 5.
How can you prove that heat is transmitted by mode of convection in liquids.
(OR)
Write an activity to show the convection in liquids.
Answer:
Aim: To demonstrate the convection of heat in liquids.

What you need:
Round bottomed flask, stand, water, potassium permanganate, straw, candle / spirit lamp.

How to do:

1. Take a round bottomed flask and fix it to a stand.
2. Now fill this flask with water.
3. Wait for some time till this water remains still.
4. Gently place some crystals of potassium permanganate in the bottom of the flask by using a straw.
5. Now slowly, heat the flask with a lighted candle or spirit lamp and observe carefully.

What you see:

1. After a few minutes the crystals of potassium permanganate dissolve in water and the coloured water will move up.
2. This is because the water at the bottom gets heated and expanded.
3. Therefore, water becomes light and moves to the top.
4. From the top, cool water comes down through the sides of the flask because it is heavier than hot water.
5. This process will continue further.
6. So, heat gets transferred from one place (bottom) to another place (top).

What you learn:

This process of transfer of heat from source of heat to surface by the motion of particles is called “convection of heat”. Here heat is transferred by means of currents called convectional currents. In liquids and gases heat is transmitted by mode of convection of heat.

Activity – 6

Question 6.
How can you prove that solid expands on heating and contracts on cooling?
Answer:

1. Take two blocks of wood of same heights.
2. Take a cycle spoke.
3. Fix one end of the rod to a wooden block with the help of plastic tape, so that it will not move.
4. Place the free end of the cycle spoke on another wooden block.
5. Take a needle and poke straw to it.
6. Place this needle between the spoke and wooden block.
7. Place 4 or 5 candles or divas under the metal rod between the blocks and light them.
8. Observe the straw carefully.
9. You will observe movement in the straw. The needle rolls on the second block of wood because of the expansion of the cycle spoke.
10. Now remove the candles or divas and observe.
11. If we remove the candles the needle rolls back causing movement in the straw oppo-site to the previous motion.
12. From this activity we can say solid expands on heating and contracts on cooling.

Activity – 7

Question 7.
How can you prove that liquids expands on heating?
Answer:

1. Take test tube and fill it with coloured water.
2. Fix a capillary tube through a rubber cork and mark the level of water on the tube.
3. Now put test tube in hot water and observe the level of water in tube.
4. Observe the difference in the level of water after heating.
5. You will observe raising in the level of water in the tube while heating
6. Stop heating and observe change in the level of water again.
7. The level of water in the tube lowering while cooling.
8. From this you can say that liquids expands on heating and contracts on cooling. (You can use injection bottle instead of test tube and empty refill instead of capilary tube.)

Activity – 8

Question 8.
How can you prove that air expands on heating? What happens when air is heated? Explain with an activity. |i
Answer:

1. Take a bottle with a small neck.
2. Attach a balloon at the neck of the bottle.
3. Place the bottle in a vessel containing water.
4. Heat the vessel and observe the size of the balloon care* fully.
5. You observe that the balloon will get inflated, because the air inside the bottle gets heated up and expands.
6. Now stop heating the bottle and remove it from hot water.
7. If needed keep it in cold water and observe the size of the balloon.
8. On cooling, you will observe deflation of the balloon.
9. Here air contracts on losing heat.
10. This activity concludes Gases (Air) expands on heating and occupies more space.
11. They contracts on cooling and occupy less space.

Activity – 9

Question 9.
How can we use laboratory thermometers? Explain with an activity.
Answer:

1. Take two bowls.
2. Take cold water in one bowl and hot water in another bowl.
3. Place the mercury bulb of the thermometer in cold water so that the bulb immerses in it.
4. Wait for some time till the mercury level shows a constant reading.
5. Note down that reading.
6. Now place the thermometer in hot water and note down the tern- perature reading.
7. Note down the temperature of the given cold water.
8. Note down the temperature of the given hot water.

Activity – 10

Question 10.
How to use a clinical thermometer? Explain with an activity.
Answer:

1. Wash the clinical thermometer properly with an antiseptic solution.
2. To lower the mercury level, hold the thermometer firmly and give some jerks.
3. Ensure that it falls below 35°C.
4. Now place the bulb of the thermometer under your friend’s tongue.
5. After one or two minutes, take the thermometer out and note the reading.
6. This is your body temperature.
7. Don’t hold the thermometer by the bulb while reading it.
8. Note down the body temperature your friend.
9. The normal temperature of the human body is 37°C or 98.4°F.

Activity – 11

Question 11.
How can you explain with an activity, that “On heating, the air expands” occupying more space and becomes lighter?
(OR)
What happens to the air on heating? Explain with an activity.
Answer:

1. Take two empty paper cups of the same size.
2. Take a broomstick.
3. Hang the two cups in the inverted position from the two ends of the broomstick using thread.
4. Tie a piece of thread in the middle of the stick. Hold the stick by the thread, like a weighing balance.
5. Put a burning candle below one of the cups as shown in the figure and observe what happens.
6. We notice that the cup above the candle flame moves up.
7. As you already know the phenomenon of convection of heat, the same phenomenon works in air.
8. Here the air above the candle gets heated up, becomes lighter and rises up.
9. This rising air pushes the paper cup.
10. On the other hand, the air under the second paper cup remains the same.
11. So, we say that “On heating, the air expands” occupying more space and becomes lighter.

Activity – 13

Question 13.
How do you show that the moving air creates low pressure with an activity?
Answer:

1. Take a glass and keep a postcard on it.
2. Wave your notebook above the postcard to displace the air just above the postcard.
3. Observe the postcard.
4. When we move our notebook, there is a movement of air.
5. The moving air creates low pressure.
6. Hence the postcard lifts up due to the higher pressure on the card from the air inside the glass.

Activity – 14

Question 14.
Collect the weather reports of any place (near your village) of the last 7 days from a newspaper or television. Record the information in the table given below.

Answer the following questions.
1. What are the measuring components of weather?
Answer:
Maximum and minimum temperature of a day, air pressure, rainfall, wind speed and humidity are called measuring components of weather.

2. What is your observations? Do all the days have the same values of components of weather?
Answer:
1 observe that, some components in the table may be the same for some days. But, all are not the same on all days. This, causes variations in atmospheric conditions.

Activity – 15

Question 15.
Classify the following sentences and write in the table given below.
1) It keeps on changing.
2) Typical weather in a region for a long period of time.
3) It affects our lifestyle.
4) It remains constant for 25 years or more.
5) It affects our daily life.

SCERT AP 6th Class Science Study Material Pdf 3rd Lesson జంతువులు – ఆహారం Textbook Questions and Answers.

AP State Syllabus 6th Class Science 3rd Lesson Questions and Answers జంతువులు – ఆహారం

6th Class Science 3rd Lesson జంతువులు – ఆహారం Textbook Questions and Answers

Improve Your Learning (అభ్యసనాన్ని మెరుగుపరచుకుందాం)

I. ఖాళీలను పూరించండి.

1. సీతాకోక చిలుకలు పుష్పాల నుండి తేనెను పీల్చుకొనుటకు …… ను ఉపయోగిస్తాయి. (ప్రోబోస్సిస్ (తుండము)
2. పులులు మాంసాన్ని మాత్రమే తింటాయి. కావున అవి …………. (మాంసాహారులు)
3. విచ్ఛిన్నకారులను ………………… అని కూడా అంటారు. (రీసైక్లర్)

II. సరైన సమాధానాన్ని గుర్తించండి.

1. ఆహారపు గొలుసులో శక్తికి మూల వనరు …….
A) ఉత్పత్తిదారులు
B) వినియోగదారులు
C) సూర్యుడు
D) విచ్ఛిన్న కారులు
జవాబు:
C) సూర్యుడు

2. కింది వాటిలో ఉభయాహారిని గుర్తించండి.
A) సింహం
B) ఆవు
C) కుక్క
D) పులి
జవాబు:
C) కుక్క

3. మానవుడ్ని ఆహారపు గొలుసులో ఏ స్థానంలో ఉంచుతావు?
A) ప్రాథమిక వినియోగదారుడు
B) ద్వితీయ వినియోగదారుడు
C) తృతీయ వినియోగదారుడు
D) పైవన్నీ
జవాబు:
C) తృతీయ వినియోగదారుడు

III. ఈ క్రింది ప్రశ్నలకు జవాబులు రాయండి.

ప్రశ్న 1.
మీ పరిసరాలలో ఉన్న ఒకే రకమైన ఆహారపు అలవాట్లు గల జంతువులను పేర్కొనండి.
జవాబు:
ఆవు, గేదె, మేక మరియు గొర్రెలు ఒకే రకమైన ఆహారపు అలవాటును కలిగి ఉంటాయి. ఎందుకంటే ఇవి శాకాహారులు. ఆహారం కోసం మొక్కల పై ఆధారపడతాయి.

ప్రశ్న 2.
కుక్కకూ, కోడికీ ఉండే కాళ్ళు, గోర్లను పోల్చండి. అవి వేరుగా ఉండటానికి గల కారణాలు రాయండి.
జవాబు:

ప్రశ్న 3.
ఆహారం తీసుకోవడానికి నాలుకను అవయవంగా ఉపయోగించే కొన్ని జంతువుల పేర్లు రాయండి.
జవాబు:
కప్పలు, బల్లులు, తోటబల్లి, ఊసరవెల్లి, ఎకిడ్నా నాలుకను ఆహారాన్ని తీసుకోవడానికి ఒక సాధనంగా ఉపయోగిస్తాయి.

ప్రశ్న 4.
కిందివాటిలో తప్పుగా ఉన్న వాక్యాలను గుర్తించి, కారణాలు రాయండి.
ఎ) నీటిలో నివసించే జంతువులన్నీ మొక్కలను మాత్రమే తింటాయి.
బి) ఏనుగులు, జింకలు అడవిలో నివసించే శాకాహారులు.
సి) పక్షుల ముక్కులు అవి వాటి ఆహారాన్ని తీసుకోవడానికి అనుకూలంగా ఏర్పడ్డాయి.
డి) వాడి అయిన గోర్లు (పంజా) వేటాడడానికి ఉపయోగపడతాయి.
ఇ) చాలావరకు ఆహారపు గొలుసులు శాకాహారులతో ముగుస్తాయి.
జవాబు:
ఎ) నీటిలో నివసించే జంతువులన్నీ మొక్కలను మాత్రమే ఆహారంగా తింటాయి.
ఈ వాక్యం తప్పు. నీటిలో చాలా జంతువులు ఇతర జంతువులను తింటూ నివసిస్తున్నాయి.
ఉదా :
సముద్రంలో నీలి తిమింగలం క్రిల్ అనేక చిన్న జంతువులను తింటుంది.

బి) ఏనుగులు, జింకలు అడవిలో నివసించే శాకాహారులు.
ఏనుగులు మరియు జింకలు అడవిలో నివసించే శాకాహారులు కాబట్టి ఈ వాక్యం సరైనది.

సి) పక్షుల ముక్కులు అవి వాటి ఆహారాన్ని తీసుకోవడానికి అనుకూలంగా ఏర్పడ్డాయి.
పక్షి ముక్కులు వాటి ఆహారపు అలవాట్లకు రూపకల్పన చేయబడినందున ఈ వాక్యం సరైనది.

డి) వాడి అయిన గోర్లు (పంజా) వేటాడడానికి ఉపయోగపడతాయి.
మాంసాహారులు పదునైన పంజాలు కల్గి ఇతర జీవులను వేటాడతాయి. కావున ఈ వాక్యం సరైనది.

ఇ) చాలావరకు ఆహార గొలుసులు శాకాహారులతో ముగుస్తాయి.
ఈ వాక్యం తప్పు.
ఆహార గొలుసు శాకాహారులతో మొదలై అగ్ర మాంసాహారులతో ముగుస్తుంది.

ప్రశ్న 5.
ఆహారపు గొలుసు యొక్క ప్రాధాన్యతను తెలపండి.
జవాబు:

1. ఆహార గొలుసు ఒక జీవి నుండి మరొక జీవికి ఆహారము ఎలా బదిలీ అవుతుందో చూపిస్తుంది.
2. ఇది ఆవరణ వ్యవస్థలో శక్తి పోషకాల రవాణాను సూచిస్తుంది.
3. ఇది ఉత్పత్తిదారులు మరియు వినియోగదారుల మధ్య సంబంధాన్ని చూపుతుంది.
4. ఇది ప్రకృతిలో విభిన్న జీవులు పరస్పరం ఆధారపడటాన్ని వివరిస్తుంది.

ప్రశ్న 6.
ఈ కింది వాటిని సరైన క్రమంలో అమర్చటం ద్వారా ఆహారపు గొలుసును రూపొందించండి.
1. కుందేలు → క్యారెట్ → గ్రద్ద → పాము
2. మానవుడు → కీటకం → శైవలం → చేప
జవాబు:

1. క్యారెట్ → కుందేలు → పాము → గ్రద్ద
2. శైవలం → కీటకము → చేప → మానవుడు

ప్రశ్న 7.
ఆహారపు గొలుసుల గురించి ఇంకా వివరంగా తెలుసుకోవడానికి ఎలాంటి ప్రశ్నలు అడిగి మీ సందేహాన్ని తీర్చుకోగలరు?
జవాబు:

• ఆహార గొలుసు అంటే ఏమిటి?
• జంతువులు మరియు మొక్కలు ఒకదానిపై ఒకటి ఎలా ఆధారపడి ఉంటాయి?
• పర్యావరణ వ్యవస్థలో శక్తి ఎలా ప్రవహిస్తుంది?
• జీవావరణ వ్యవస్థకు, జంతువుల ఆహార అలవాట్లకు ఏదైనా సంబంధం ఉందా?
• ప్రకృతి పర్యావరణ వ్యవస్థను ఎలా సమతుల్యం చేస్తుంది?
• ఆహార గొలుసు ఎప్పుడూ మొక్కలతో ఎందుకు మొదలవుతుంది?

ప్రశ్న 8.
భూమిపై విచ్ఛిన్నకారులే లేకుంటే ఏమౌతుంది?
జవాబు:

• చనిపోయిన మొక్కలు మరియు జంతువులను విచ్చిన్నం చేయడం ద్వారా బాక్టీరియా మరియు శిలీంధ్రాలు ఆహారము పొందుతాయి. కాబట్టి వాటిని విచ్ఛిన్నకారులు అంటారు.
• పర్యావరణంలోని పదార్థాలు తిరిగి భూమిని చేరటానికి ఇవి సహాయపడతాయి.
• విచ్ఛిన్నకారులు లేనట్లయితే చనిపోయిన మరియు వ్యర్థ పదార్థాలు భూమిపై ఉంటాయి.
• పోషకాలు తిరిగి నేలను చేరవు.
• నేలలోని పోషకాలు భర్తీ చేయబడవు.
• చనిపోయిన జీవులు భూమిపైనే ఉండడం వల్ల, భూమిపై జీవ మనుగడ అసాధ్యం.

ప్రశ్న 9.
మీకిష్టమైన ఏదో ఒక ఆహారపు గొలుసును గీయండి.
జవాబు:

ప్రశ్న 10.
ఆహారపు గొలుసులో ఉత్పత్తిదారుల పాత్రను నీవు ఎలా అభినందిస్తావు?
జవాబు:

• మొక్కలను ఉత్పత్తిదారులు అని పిలుస్తారు. ఎందుకంటే అవి తమ ఆహారాన్ని సొంతంగా తయారు చేసుకుంటాయి. పర్యావరణ వ్యవస్థలోని అన్ని జీవులకు ఆహారాన్ని అందించే ఏకైక జీవులు ఈ మొక్కలే.
• పర్యావరణ వ్యవస్థలో, ఉత్పత్తిదారులు అన్నీ ఆహార గొలుసు యొక్క ఆధారం.
• మొక్కలు ఆహారాన్ని మాత్రమే కాకుండా భూమికి ఆక్సిజన్‌ను కూడా అందిస్తాయి.
• భూమిపై జీవితాన్ని కొనసాగించడానికి మొక్కలు విలువైనవి.

కృత్యాలు

కృత్యం – 1

6th Class Science Textbook Page No. 22

ప్రశ్న 1.
పట్టికలో వివిధ జంతువుల జాబితా ఇవ్వబడింది. వాటిలో కొన్నింటికి అవితినే ఆహారం కూడా ఇవ్వడం జరిగింది. మిగిలిన పట్టికను నింపండి.

జవాబు:

పట్టిక ఆధారంగా కింది ప్రశ్నలకు సమాధానం ఇవ్వండి.
1. ఆహారం కోసం మొక్కలు వాటి ఉత్పత్తుల పైన మాత్రమే ఆధారపడే జంతువులేవి?
జవాబు:
గేదె, ఆవు, సీతాకోకచిలుక.

2. జంతువులు, వాటి ఉత్పత్తులను మాత్రమే ఆహారంగా తీసుకునే జంతువులేవి?
జవాబు:
పిల్లి, సింహం, పులి, బల్లి, సాలీడు.

3. ఆహారం కోసం మొక్కలు, జంతువులు రెండింటిపై ఆధారపడే జంతువులేవి?
జవాబు:
ఎలుక, కాకి, మానవులు మరియు ఇతరాలు.

కృత్యం – 2

6th Class Science Textbook Page No. 23

ప్రశ్న 2.
పట్టికలో ఇచ్చిన జంతువులు ఆహారాన్ని గుర్తించడానికి, సేకరించడానికి ఉపయోగించే శరీర భాగాలను రాయండి.

జవాబు:

• ఆహారం తినడానికి ఏయే జంతువులు ఒకే రకమైన భాగాలను ఉపయోగిస్తాయి?
జవాబు:
1) కప్ప 2) పాము 3) బల్లి 4) కుక్క 5) ఆవు ఆహారం తినడానికి నాలుకను ఉపయోగిస్తాయి.

• ఆహారం కొరకు కుక్క ఉపయోగించిన భాగాలను, కప్ప ఉపయోగించిన భాగాలతో పోల్చండి. వాటి మధ్య మీరు, గమనించిన పోలికలు, భేదాలను నమోదు చేయండి.
జవాబు:

• కుక్క, కప్ప ఆహారం తీసుకోవడానికి నాలుకను అవయవంగా ఉపయోగించుకుంటాయి.
• కుక్క నాలుకనుపయోగించి నీరు త్రాగుతుంది. కప్ప నాలుకను ఉపయోగించి కీటకాలను పట్టుకొని మింగుతుంది.
• వాసన ఆధారంగా కుక్క తన ఆహారాన్ని పసిగడుతుంది. కప్ప తన నోటితో గాని, నాలుకతో గాని కీటకాలను పట్టుకొని తింటుంది.

• కోడి, పిచ్చుక ఆహారం తీసుకోవడంలో ఉపయోగించే భాగాలను పోల్చండి. మీరు గమనించిన పోలికలు, వ్యత్యాసాలు రాయండి.
జవాబు:

• కోడి, పిచ్చుక రెండూ పురుగులు మరియు గింజలను ఆహారంగా తీసుకుంటాయి.
• ఆహార సేకరణలో కోడి తన శరీర భాగాలైన ముక్కు, కాళ్ళు ఉపయోగిస్తుంది. పిచ్చుక ఆహారాన్ని చూసి ముక్కుతో ఏరుకుని తింటుంది.

• కుక్క, సింహం ఆహార సేకరణలో ఉపయోగించే భాగాలలో పోలికలేమైనా గుర్తించారా?
జవాబు:

• కుక్క, సింహం రెండూ కూడా మాంసం తింటాయి.
• రెండింటికి చూపు బాగుంటుంది. అవి పదునైన వాటి గోర్లతో ఆహారాన్ని పట్టి ఉంచుతాయి.
• మాంసాన్ని చీల్చడంలో పదునైన వాటి పళ్ళను ఉపయోగిస్తాయి.
• సింహం ఒంటరిగా వేటాడుతుంది. ఆహారం దొరికిన చోట తింటుంది.
• కుక్క శాకాహారం కూడా తింటుంది.

• ఆహారం తీసుకునే విధానంలో గ్రద్దకూ, సింహానికి ఉండే పోలికలు, వ్యత్యాసాలు రాయండి.
జవాబు:

• సింహం, గ్రద్ద రెండూ మాంసాహారులే.
• ఈ రెండూ పదునైన వాటి కాలి గోళ్లతో మాంసాన్ని చీల్చుతాయి.
• సింహం నేలమీద జంతువులను వేటాడుతుంది.
• గ్రద్ద ఆకాశంలో ఎగురుతూ నేలమీది ఆహారాన్ని చూసి కిందకు దిగి తింటుంది.

కృత్యం – 3

6th Class Science Textbook Page No. 25

ప్రశ్న 3.
ఇవ్వబడిన పటాన్ని పరిశీలించండి. వివిధ రకాల పక్షుల ముక్కులు వివిధ రకాలుగా ఉన్నాయి. పక్షుల ముక్కుల్లో వైవిధ్యానికి కారణమేమిటో మీకు తెలుసా?

జవాబు:

• ముక్కులు భిన్నంగా ఉంటాయి ఎందుకంటే పక్షులు వివిధ రకాల ఆహారాన్ని తింటాయి.
• కాబట్టి, ముక్కుల రకం వాటి ఆవాసాలు, పర్యావరణం మరియు ఆహార అలవాట్లపై కూడా ఆధారపడి ఉంటుంది.
• పక్షుల ముక్కులు ఎరను చంపడానికి, పోరాడటానికి, ఆహారాన్ని పొందడానికి మరియు వారి పిల్లలను పోషించడానికి వాటికి సహాయపడతాయి.
• వాటి ఆహారపు అలవాట్ల ఆధారంగా పక్షులు బలమైన కొక్కెము ముక్కు పొడవైన ముక్కు పొడవైన, సన్నని ముక్కు మొదలైన రకాల ముక్కులను కలిగి ఉంటాయి.

కృత్యం – 4

6th Class Science Textbook Page No. 26

ప్రశ్న 4.
బల్లి ఆహారాన్ని ఎలా పట్టుకుంటుంది? మీ పరిశీలనలను వివరంగా రాయండి.
జవాబు:

• ఆహారాన్ని వేటాడటానికి బల్లి తన దృష్టిని ఉపయోగిస్తుంది.
• బల్లి తన దృష్టిని కీటకాల కదలికలపై కేంద్రీకరిస్తుంది.
• బల్లి, పురుగు వైపు చాలా వేగంగా కదులుతుంది.
• ఇది నాలుకను ఉపయోగించడం ద్వారా కీటకాన్ని పట్టుకుని తింటుంది.

• కప్ప, బల్లి ఆహారం తీసుకునే విధానంలో భేదాలు తెలుసుకోండి. ఈ జంతువులు నాలుకను ఎలా ఉపయోగిస్తాయి?
జవాబు:

కృత్యం – 5

6th Class Science Textbook Page No. 26

ప్రశ్న 5.
ఆవు లేదా బర్రె (గేదె) ఆహారం తీసుకునేటప్పుడు గమనించి మీ పరిశీలనలు నోటుపుస్తకంలో రాయండి.
• ఆవు ఆహారాన్ని ఎలా సేకరిస్తుంది?
జవాబు:
వాసనను చూడడం ద్వారా ఆవు తన ఆహారాన్ని కనుగొంటుంది.

• అందుకోసం ఏయే శరీర భాగాలను ఉపయోగిస్తుంది?
జవాబు:
ఆవు ఆహారం తీసుకోవటానికి నోరు, దంతాలు మరియు నాలుకను ఉపయోగిస్తుంది.

• ఆవు తినడం ఎలా మొదలు పెడుతుంది?
జవాబు:
వాసన, చూపు ఆధారంగా ఆవు ఆహారం సేకరిస్తుంది. ఆహారం కోసం ఆవు దవడలు, పళ్ళు నాలుక, నోరు ఉపయోగిస్తుంది. ఆహారాన్ని ఆవు గబగబా నమిలి మింగుతుంది. దానిని తన జీర్ణాశయంలో ఒక భాగంలో నిలవ చేస్తుంది.

• ఆవులకు దంతాలుంటాయా? రెండు దవడలకూ దంతాలుంటాయా?
జవాబు:
అవును. ఆవులకు రెండు దవడలపై దంతాలు ఉంటాయి. కానీ ముందు పళ్ళు ఉండవు.

• ఆవు శాకాహారి అని నీవు ఏ విధంగా నిర్ణయిస్తావు?
జవాబు:
ఆవు ఆహారం కోసం మొక్కలు మరియు మొక్కల ఉత్పత్తులపై మాత్రమే ఆధారపడి ఉంటుంది. ఇవి ఆకుపచ్చ / పొడిగడ్డి, ఆకులు, కొమ్మలు మరియు పండ్లు వంటి మొక్కల యొక్క వివిధ భాగాలను తింటాయి. తద్వారా ఆవు శాకాహారి అని చెప్పగలను.

• ఆవులు, గేదెలు చెట్ల క్రింద కూర్చొని దవడలు కదిలించడం చూసే ఉంటారు. అలా ఎందుకు చేస్తాయో మీకు తెలుసా?
జవాబు:
ఆవు మరియు గేదె ఆహారాన్ని చాలా త్వరగా నమిలి, మింగిన తరువాత వాటి కడుపులో ఒక భాగంలో నిల్వ చేసుకొంటాయి. కొంత సమయం తరువాత, ఇవి కడుపు నుండి నోటికి ఆహార పదార్థాన్ని తిరిగి తెచ్చి, మళ్ళీ తీరికగా నములుతాయి. దీనినే నెమరు. వేయటం అంటారు.

కృత్యం – 6

6th Class Science Textbook Page No. 27

ప్రశ్న 6.
మీ పరిసరాలలో కుక్కను గమనించండి. ఆహారం ఎలా సేకరిస్తుందో గమనించండి. పరిశీలనలను రాయండి.

• కుక్క ఆహారాన్ని ఎలా పసిగడుతుంది?
జవాబు:
కుక్క వాసన ద్వారా తన ఆహారాన్ని కనుగొంటుంది. కుక్కల ముక్కు మన కంటే వెయ్యి రెట్లు ఎక్కువ సున్నితమైనది.

• ఆహారం తీసుకోవటంలో ఏ భాగాలు సహాయపడతాయి?
జవాబు:
నోరు మరియు నాలుక ఆహారాన్ని తీసుకోవడంలో పాల్గొంటాయి.

• కుక్క మాంసాన్ని ఎలా తింటుంది?
జవాబు:
కుక్క ఇతర జంతువులను తన కాళ్ళతో పట్టుకుంటుంది. ఇది పదునైన దంతాలను ఉపయోగించి మాంసాన్ని చీల్చి తింటుంది. ఇది మాంసాన్ని, దంతాల సహాయంతో నమిలి, నాలుకను మింగడానికి ఉపయోగిస్తుంది.

• కుక్క నీరు ఎలా త్రాగుతుంది?
జవాబు:
కుక్క తన నాలుకతో నీటిని లాక్కుని త్రాగుతుంది.

• కుక్క నాలుకను ఉపయోగించే విధానానికి, కప్ప లేదా ఆవు నాలుకను ఉపయోగించే విధానానికి ఏమైనా తేడా ఉందా? కింద ఇవ్వబడిన ఖాళీల్లో రాయండి.

జవాబు:

కృత్యం – 7

6th Class Science Textbook Page No. 28

ప్రశ్న 7.
చిత్రాన్ని గమనించండి మరియు క్రింది ప్రశ్నలకు సమాధానం ఇవ్వండి.
• ఆహారపు గొలుసులో శక్తికి మూలవనరు ఏమిటి?
జవాబు:
సూర్యకాంతి ఆహారపు గొలుసులో శక్తికి మూలం.

• మిడత దాని శక్తిని ఎలా పొందుతుంది?
జవాబు:
ఆహార గొలుసులో మిడత ఒక ప్రాథమిక వినియోగదారు. కాబట్టి ఇది ఆహారం కోసం గడ్డిపై ఆధారపడి ఉంటుంది.

• ఆహారపు గొలుసు నుండి కప్ప తొలగించబడితే కాకికి ఏమవుతుంది.?
జవాబు:
ఈ ఆహార గొలుసులో కప్ప, మిడతను తినే ద్వితీయ వినియోగదారు. ఈ ఆహార గొలుసులో కప్ప తొలగించబడితే, మిడత జనాభా పెరుగుతుంది. కాకి, కప్పలను తినే తృతీయ వినియోగదారు. ఈ ఆహార గొలుసులో కప్పను తొలగించినట్లయితే, కాకులు ఆకలితో చనిపోతాయి మరియు వాటి జనాభా తగ్గుతుంది.

• ఇచ్చిన చిత్రంలో పుట్టగొడుగు పాత్ర ఏమిటి?
జవాబు:
పుట్టగొడుగు ఒక శిలీంధ్రము. చనిపోయిన పదార్థం విచ్ఛిన్నం చేయడం ద్వారా పుట్టగొడుగు ఆహారాన్ని పొందుతుంది.

ఇవి వ్యర్థ పదార్థాలను విచ్ఛిన్నం చేస్తూ విచ్ఛిన్నకారులుగా పని చేస్తాయి.

ప్రాజెక్ట్ పనులు

6th Class Science Textbook Page No. 31

ప్రశ్న 1.
కొంగలు ఎక్కువగా కనిపించే సమీపంలోని కొలను దగ్గరకు వెళ్ళండి. అవి చేపలు పట్టే విధానాన్ని గమనించి రాయండి. (నీటి తావుల దగ్గరకు వెళ్ళినపుడు జాగ్రత్తగా ఉండాలి. అలాంటి చోట్లకు వెళ్లినప్పుడు పెద్దవారి సహాయం తీసుకోండి.)
జవాబు:

• కొంగలు సాధారణంగా సరస్సులలో కనిపిస్తాయి మరియు చేపలు దానికి ఆహారం.
• దానికి ఉన్న పొడవాటి సన్నని కాళ్ళు నీటిలో ఇబ్బంది కలగకుండా కదలడానికి సహాయపడతాయి.
• చేపలను పట్టుకునేటప్పుడు కొంగ చాలా నెమ్మదిగా కదలడానికి ప్రయత్నిస్తుంది.
• కాబట్టి చేపలకు దాని ఉనికి తెలియదు.
• ఒక్కోసారి అది చేపల వేట కోసం చాలా కాలం పాటు నిలబడవలసి వస్తుంది దీనినే కొంగ జపం అంటారు.
• కొంగ దాని పొడవైన ముక్కు సహాయంతో చేపలను వేగంగా పట్టుకుంటుంది.

ప్రశ్న 2.
ఒకటి లేదా రెండు వానపాములను సేకరించి తడిమట్టి గల సీసాలో వేయండి. రంధ్రాలు గల మూతతో సీసాను మూయండి. వానపాము ఆహారం ఎలా తీసుకుంటుందో గమనించండి. మీ పరిశీలనలను నమోదు చేయండి.
జవాబు:
లక్ష్యం :
తడి నేలలో వానపాములు ఆహారం తీసుకొనే చర్యను గమనించడం.

మనకు కావలసినది :
రెండు వానపాములు, ఒక గాజు సీసా, తడి మట్టి.

ఏమి చేయాలి :
ఒక గాజు సీసా తీసుకొని కొంత తడి మట్టితో నింపండి. ఇప్పుడు మట్టితో నిండిన సీసాలో రెండు వానపాములను ఉంచండి. కొంతకాలం వాటిని గమనించండి.

మనం ఏమి చూస్తాము :
వానపాములు తక్కువ పరిమాణంలో మట్టిని తినడం ప్రారంభించాయని మనం గమనించవచ్చు.

మనం నేర్చుకున్నవి :
పై పరిశీలనలతో వానపాములు పోషకాలను కలిగి ఉన్న తేమతో కూడిన మట్టిని తింటాయని మనం నిర్ధారించాము.

ప్రశ్న 3.
కింది పట్టికను పూరించండి.

జవాబు:

ప్రశ్న 4.
మీ సొంత ఆహారపు గొలుసును తయారుచేసి, మీ తరగతి గదిలో ప్రదర్శించండి.
జవాబు:
విద్యార్థి కృత్యం : మొక్క → గొంగళీ → ఊసరవెల్లి → పాము → ముంగిస
(ఈ ఆహార గొలుసు ఆ జంతువుల రేఖాచిత్రాలతో తయారు చేయవచ్చు).

ప్రశ్న 5.
జంతువుల చిత్రాలు సేకరించి వాటిని శాకాహార, మాంసాహార, ఉభయాహార జంతువులుగా వేరుచేసి పుస్తకంలో అంటించి స్క్రిప్ బుక్ తయారుచేయండి.
జవాబు:
ఉదా :

SCERT AP 7th Class English Textbook Answers 4th Lesson The Brave Little Bowman Textbook Questions and Answers.

AP State Syllabus 7th Class English Unit 4 Questions and Answers The Brave Little Bowman

7th Class English Unit 4 The Brave Little Bowman Textbook Questions and Answers

Look at the picture below and answer the questions that follow.

Question 1.
What are the men doing?
Answer:
The men are fighting.

Question 2.
What weapons are they using?
Answer:
The men are using maces (gadha) to fight.

Question 3.
Where do we see such fight scenes?
Answer:
We see such fight scenes in wars during the times of kings.

Question 4.
Can you name soma world famous personalities from any field?
Answer:
Yes, I can name some world famous personalities. For example, Virat Kohli from cricket, Kalam from science and technology, Narendra Modi from politics, P.V.Sindhu from tennis.

Question 5.
Is it their appearance/skill that makes them great personalities?
Answer:
It is their skill that makes them great.

Questions Given In The Lesson

Possible answers to the questions given in the middle of the lesson :

Question 1.
Do you know the success story of Sudha Chandran? Discuss.
Answer:
Yes, I know the success story of Sudha Chandran. She is an Indian film actor and a famous Bharatanatyam dancer. She overcame her disability of losing her right leg in an accident and danced again with great courage and determination.

Question 2.
Collect the names of such personalities and share with your friends.
Answer:
Albert Einstein, Stephen Hawking, George Washington, Helen Keller, Franklin D.Roosevelt, Ludwig Van Beethoven, Nik Vujicic, Rowan Atkinson, Walt Disney are some of the successful personalities with disabilities. They proved that their disability couldn’t stop them from achieving their goals.

Question 3.
Can the big man win the battle ? Substantiate your answer.
Answer:
I think the big man can’t win the battle as he is not a skilled warrior.

Question 4.
Will the little man support the big man?
Answer:
Yes, the little man will support the big man.

Reading Comprehension

A. Answer the following questions.

Question 1.
Why didn’t the little bowman go to the king and ask for a job in the army?
Answer:
The little bowman was afraid that the king would reject him as he was short and had a crooked back.

Question 2.
What did the little bowman tell the big man to do when he saw him digging ditches?
Answer:
The bowman approached him and said, “The days of your misery are over! You will immediately be recruited in the army because of your physique and you can then introduce me to them as your assistant. I will do the work that you will be given to do and we shall divide the pay between’us. This way both of us will be able to live comfortably.”

Question 3.
How did the big man introduce the little man to the king?
Answer:
The big man introduced the little man to the king as his assistant.

Question 4.
Did the big man kill the tiger and the wild elephant? Who killed them?
Answer:
No, the big man did not kill the tiger and the wild elephant. The little bowman killed them with his skill in archery.

Question 5.
If you were the big man, what would you do in the battlefield?
Answer:
If I were the big man, I would not leave the battlefield. As I knew the skill of the little bowman in archery, I would stay on the elephant and finish the battle.

Question 6.
Did the running away of the big man from the battlefield benefit the little man? How?
Answer:
The running away of the big man from the battlefield benefited the little man undoubtedly. The little man got a change to prove his skill and power. He was recognized by the king and received the much-deserved honour at last.

B. Put the following sentences in the order of events.

The big man and the little man joined the king’s army.
The little man told the big man to ask the king to let him join the army.
The little man saw a big strong man digging a ditch.
The big man slipped off the war elephant’s back and ran off into the city.
The little man killed the tiger and the wild elephant.
Answer:
The big man and the little man joined the king’s army. (3)
The little man told the big man to ask the king to let him join the army. (2)
The little man saw a big strong man digging a ditch. (1)
The big man slipped off the war elephant’s back and ran off into the city. (5)
The little man killed the tiger and the wild elephant. (4)

C. Say whether the following statements are True or False.

1. The little bowman introduced the big man as his assistant to the king.
2. The little man killed the tiger arid the wild elephant.
3. The big man asked the king to pay him five hundred pieces a month.
4. The little bowman led the elephant into the battle and won the battle.
5. The king made the little bowman the chief of his army and gave him rich gifts
Answer:

1. False
2. True
3. False
4. True
5. True

Correct the false statements and write them here.
1. The big man introduced the little bowman as his assistant to the king.
3. The king told the big man that he would give a thousand silver coins a month.

Vocabulary

A. Crossword Puzzle
Fill the puzzle using the clues given below.
Across
1. an archer
3. sudden uncontrollable fear or anxiety
5. unkind, severe
6. having knowledge or ability
2. a brave soldier
3. express warm approval or admiration .
4. bent or twisted out of shape
7. a narrow channel dug at the side of the road or field

Answer:

B. Observe how the past and past participle forms of the verbs are formed in set I and set II.

Note:
Verbs such as walk, ask, join, etc, which you find in set I are Regular Verbs.
Verbs such as take, drive, give, etc, which you find in set II are Irregular Verbs.
Pick out the verbs from the lesson, and write the V2 (past) and V3 (past participle) forms and place them under proper headings.

C. Find the ‘antonyms / opposites’ for the given words from the reading text.

1. unarmed
2. foolish
3. unskilled
4. relaxed
5. coward
6. separate
7. gentle
8. proud
9. straight
10. dismount

Antonyms:

1. unarmed × armed
2. foolish × wise
3. unskilled × skilled
4. relaxed × disturbed
5. coward × brave
6. separate × join
7. gentle × harsh
8. proud × humble
9. straight × crooked
10. dismount × mount

D. Fill in the blanks with the opposite of the word underlined.

1. Never speak harshly, always speak _________ .
2. Cruelty towards animals is a sin. We should show _________ to animals.
3. Everybody likes to be praised. Nobody likes to be _________ .
4. I am glad I got the job, but _________ on leaving my home town.
5. David told his timid young brother to be _________ .
Answer:

1. Never speak harshly, always speak kindly.
2. Cruelty towards animals is a sin. We should show kindness to animals.
3. Everybody likes to be praised. Nobody likes to be blamed.
4. I am glad I got the job, but sad on leaving my home town.
5. David told his timid ybimg brother to be brave.

Grammar

Read the following sentences from the reading text.

• The king will take both of us.
• We will go to the king and ask for a job.
• Will you come with me?

These sentences are in the simple future tense.
Pick out some more sentences which are in the simple future tense from the reading text and write them here. .
1. ___________
2. ___________
3. ___________
4. ___________
5. ___________
6. ___________
Answer:
1. I will do the work assigned to you and we will divide the pay equally.
2. Okay, 1 will go with you.
3. I will take the both of you and give a thousand silver coins a month.
4. We will serve you to the best of our abilities.
5. Will you do it?
6. I will kill the tiger.
7. I will sit behind you on the war elephant and shoot with my bow and arrow.
8. I will fight for the king.

You have already learnt the structure and usage of simple future tense. Now, do the following exercise.

A. Here is how Karim, John and Indu plan their summer holidays.

Fill the blanks with suitable form of verb given in brackets.

1. Hello, I am Karim. Every summer we _______ (go) to Chennai to visit my grandparents. But this summer, we _______ (not visit) them. We _______ (go) on a tour to Singapore. We _______ (do) a lot of shopping there. We _______ (visit) all the sight-seeing places in Singapore. We _______ (stay) there for ten days.
Answer:
Hello, I am Karim. Every summer we go to Chennai to visit my grandparent But this summer, we will not visit them. We will go on a tour to Singapore. We will d0 of shopping there. We will visit all the sight-seeing places in Singapore. We will stay there for ten days.

2. Hello, 1 am John. This summer ______ (go) camping with my classmates and we ______ (climb) up trees. We ______ (make) campfires and ______ (sleep) in tents. But it ______ (last) only for a week. Then, like every summer. I ______ (read) books and ______ (watch) TV at home.
Answer:
Hello, I am John. This summer I will go camping with my classmates and we will climb up trees. We will make campfires and will sleep in tents. But it will last only for a week. Then, like every summer I will read books and will watch TV at home.

3. Hi, I am Indu. Every summer we ______ (go) to my grandpa’s village. He has a lovely farm. This summer too, we ______ (go) there. I ______ (ride) a horse. I ______ (climb) trees and ______ (go) fishing and (pick) up flowers also. I ______ (feed) the lovely animals.
Answer:
Hi, 1 am Indu. Every summer we go to my grandpa’s village. He has a lovely farm. This summer too, we will go there. I will ride a horse. I will climb trees and will go fishing and pick up flowers also. I will feed the lovely animals.

B. Fill the blanks with the verb in simple future tense. (One is done for you)
Ex : He ______ (come) tomorrow.
A. He will come tomorrow. ‘

1. Karim ______ (travel) around Europe next year.
2. The exams ______ (be) in June.
3. The students ______ (finish) the English project in two days.
4. He ______ (call) me tomorrow afternoon.
5. I ______ (get) you something to drink.
Answer:
1. Karim will travel around Europe next year. .
2. The exams will be in June.
3. The students will finish the English project in two days.
4. He will call me tomorrow afternoon.
5. I will get you something to drink.

C. Write negative sentences for the given positive sentences. (One is done for you.)
Ex : They will go shopping on Saturday.
A. They will not go shopping on Saturday.

1. My mother will assign work to me.
Answer:
My mother will not assign work to me.

2. He will get the job.
Answer:
He will not get the job.

3. We shall buy another house.
Answer:
We shall not buy another house.

4. The doctor will see you very soon.
Answer:
The doctor will not see you very soon.

5. He will leave tomorrow.
Answer:
He will not leave tomorrow.

D. Framing questions that take Yes/No responses
Read the following sentences from the story.
Little Man : Can’t you find some other work?
Big Man : No, I can’t.
The King : Have you heard about the wild elephant?
Big Man : Yes, your Majesty.
The King : You must go to the forest and kill the tiger. Will you do it?
Big Man : Yes, your Majesty! I will kill the tiger.

Look at the answers to the above questions. Those answers begin with either YES or NO.

The above questions begin with words can, have, will, did etc. (The Auxiliary Verbs). Now let us see how these questions are framed.

1. Observe the position of the auxiliary verb in the statement and the question.

Now, frame questions to the given statements. (One is done for you)
1. He was a skilled archer.
Answer:
Was he a skilled archer?

2. The king will take both of them.
Answer:
Will the king take both of them?

3. I am not a skilled warrior.
Answer:
Am I not a skilled warrior?

4. She is preparing dinner for us.
Answer:
Is she preparing dinner for us?

5. The little girl can tell the names of all Indian Presidents.
Answer:
Can the little girl tell the names of all Indian Presidents?

6. My friends are going on an excursion.
Answer:
Are my friends going on an excursion?

7. They were building a house by this time last year.
Answer:
Were they building a house by this time last year?

8. I should attend the meeting.
Answer:
Should I attend the meeting?

9. We shall take up the challenge.
Answer:
Shall we take up the challenge?

10. The Prime Minister has declared the lockdown.
Answer:
Has the Prime Minister declared the lockdown?

2. Observe the following Statements and Questions.

Now, frame questions for the given statements: (One is done for you)

1. The rainbow appears in the sky.
Answer:
Does the rainbow appear in the sky?

2. The Sun rises in the east.
Answer:
Does the Sun rise in the east?

3. Trees give us fruits.
Answer:
Do trees give us fruits?

4. He wrote a novel.
Answer:
Did he write a novel?

5. She sang a song on the dais.
Answer:
Did she sing a song on the dais?

Writing

A. In the story the big man was appreciated for killing the tiger and the wild elephant. He started ignoring the little bowman. Describe the feelings of the little bowman in this context.

Make use of the following hints.

Unlucky I am – with my skill – killed the tiger – killed the wild elephant – but credit went to the big man – the king and the people praised him — I was ignored – really unfortunate – what can I do now? – can I reveal the truth — may the king punish us – better to keep quiet.
Answer:
How unlucky I am! I killed the tiger and the wild elephant with my skill. But the credit went to the big man. I did not get any recognition. The king and the people praised him but I was ignored. It is really unfortunate. What can I do now? Can I reveal the truth? The king may punish us if I reveal the truth. So it is better to keep quiet.

B. You have read the lesson ‘The Brave Little Bowman’. Rewrite it in the form a story.
Answer:
Once upon a time, there lived a bowman. He was a skillful archer in a city. Though he was short in height and had a crooked back, none could beat him in archery. One day he thought, “ I am good enough to join the king’s army, but he would never take me in because of my short stature and hunched back. I must look for someone tall and pow¬erful, and then I can enter the king’s army as his page.”

One day, the little bowman found the kind of man he was Iooking for. He was a tall and powerful man and used to dig ditches to earn his living. The bowman approached him and said, “The days of your misery are over! 1 am the best archer of this country and worthy of being a part of the king’s royal army. But, I may get rejected because of my height and crooked back. So, I need your help. You will immediately be recruited in the, army because of your physique and you can then introduce me to them as your assistant. I will do the work that you will be given to vdo and we shall divide the pay between us. This way both of us wili be able to live comfortably.”

The tall man gladly agreed. Together they reached the king’s palace and sent word to the king that a famous bowman was there to meet him. The king met the bowman and being impressed by his towering personality, joined him in the royal army. The little man’s dream had come true. He was now a part of the royal army, though disguised as the assistant of the big man.

In those days, there was a man-eater tiger on the loose in the jungle. The king sent for the big man and ordered him to kill the tiger. The big man told the little bowman what the king had said. They went to the forest together and soon, the little bowman shot the tiger dead. The king was extremely impressed by the heroic act of the big man and rewarded him with expensive gifts.

Some days, later, a wild elephant came on the city roads and started killing the people. The big man was asked to go and kill the elephant. The big man carried the little bowman on his shoulders and as always, the little bowman hit his target and killed the elephant.The king was full of praise for the big man and gave him a reward. The big man started treating the little man as his servant and spoke him Very rudely. The little bowmah was very sad.

A few days later, the king of the neighbouring country attacked the kingdom. The king at once sent his army. The big man was mounted on a majestic elephant and was wearing shining armour. The little bowman knew that the big man could not shoot, so he also took his bow and arrow and quietly sat behind the big man on the elephant.

When the big man saw a huge enemy army in front of him, he started to shake with fear. The little bowman asked him to keep sitting quietly, but the big man was so nervous that he jumped off the elephant and ran back to the city from the battle-field.

The little bowman led the elephant fearlessly into the battle-field and killed many of the enemies with his unmistakable shots. All the soldiers were motivated by the little man’s act of bravery and they soon forced the enemy army to withdraw, itself. The king now understood that it was the little bowman who was the real hero. He made ‘ him the chief of his army andalso rewarded him with rich gifts.

Talking Time

Language Function : Offering and asking for help:

Read the-following conversation between Gowtham and Sudha. Work in pairs.

Gowtham : Hello ! Sudha. What will you do tomorrow?
Sudha : I’ll work on my English project.
Gowtham : Shall I help you to complete your project work?
Sudha : I’ll be glad if you can.
Gowtham : Certainly, Sudha.
Sudha : Thank you very much.

Here are some examples for asking for help / offering help :

Frame sentences to make offers using the words given and practice.
1) Cook the dinner (Shall) ___________________
2) Clean the floor (Can) ___________________
3) Cup of coffee (Would) ___________________
4) Do the shopping (Will) ___________________
5) Make some sandwiches (Would) ___________________
Answer:
Making Offers:

1. Shall I cook dinner for you?
2. Can I clean the floor?
3. Would you like me to give you a cup of coffee?
4. Would you like me to make some sandwiches for you?

Asking for Help:

1. Can you clean the floor for me?
2. Will you do’shopping for me?
3. Would you mind making some sandwiches for me?

Listening

Listen to the story and answer the questions that follow.

AN AUDACIOUS VILLAGE

Every country is protected by the armed forces like the army, the navy and the air force. If one wants to join the armed forces, one needs bravery and patriotism. You may have many professionals like engineers, doctors, lawyers, teachers, etc., in your locality. However it is rare to find people who work in the army from your area.

Madhavaram, called Military Madhavaram in West Godayari District, which is famous for sending men to serve in the armed services for centuries. Almost every household in the small village has at least one member serving in the armed forces.

During colonial rule, youth from the village flocked to the military and participated in major wars. Nearly 90 soldiers from this remote village participated in World War I and the figure rose up to 1,110 in World War II. Many soldiers from this village have laid down their lives.

Soldiers from the village have been a part of every war that independent India has fought. Many soldiers from this village sacrifice and guard the Indian frontiers. The girls in the village prefer to marry military men. The villagers, to commemorate the sacrifice and services of the soldiers, built a memorial for soldiers on the lines of New Delhi’s Amar Jawan. For many years, joining the Indian Armed Forces has remained the career of choice for the young men of the village.

Answer the following questions :
1. What qualities are required to join the Armed forces?
Answer:
Bravery and patriotism .

2. Whom do the girls in the village prefer to marry?
Answer:
Military men

3. How did the villagers commemorate the sacrifice made by the soldiers?
Answer:
By building memorials for soldiers on the lines of New Delhi’s Amar Jawan

4. How many World Wars are mentioned in the story?
Answer:
Two

5. What is Amar Jawan famous for?
Answer:
It is famous for building memorials for soldiers.

Study Skill

A. Study the following pie-chart and answer the questions that follow.

1. What is the pie chart about?
Answer:
The pie chart is about the recommended diet.

2. What is the percentage of vegetables in the diet recommended?
Answer:
18%

3. _______ occupied 9% of the diet recommended.
a) Vegetables
b) Grains
c) Other
Answer:
b) Grains

4. Which item occupies the highest percentage of our diet?
a) Protein
b) Fruit
c) Vegetables
(Note : The question is wrongly given in textbook. Hence, it has been changed for the convenience of students.)
Answer:
b) Fruit

5. Identify the true/false statement.
a) The percentage of fruit in our diet is 23%. (false)
b) Grains occupy the least perccentage of our diet. (false)
c) Vegetables occupy 18% share of our diet. (true)

B. Dictionary Entry

Fun Time

Look at the word ‘make’. By replacing the underlined letter ‘k’ in the word with r, l and t we can make new words like ‘mare, male, mate’ and so on. Now make at least three new words by replacing the letter underlined with any letter of your choice.
make – mare male mate
1) same – _______
2) poke – _______
3) robe – _______
4) sail – _______
5) bake – _______
Answer:

1. safe, sage, sake, sale, same, sane, sate, save
2. pole, pone, pope, pore, pose
3. rode, role, Rome, rope, rose, rote, rove
4. bail, fail, hail, jail, mail, nail, pail, rail,.sail, tail, vail, wail
5. babe, bade, bale, bane, bare, base

Riddles:

Here are some riddles for you to solve. (One is done for you.)
Ex. I am tall when I am young and 1 am short when I am old. What am I?
A. Candle

1) You walk into a room that contains a candle, a kerosene lamp, a match and a fireplace. What would you light first?
2) A man dies of old age on his 25th birthday. How is this possible?
3) What has many keys but can’t open, a single lock?
4) What is black when it is clean and white when it is dirty?
5) Where does today come before yesterday?
Answer:
1) A match
2) The man’s birthday falls on February 29.
(Or)
The man was born on February 29.
3) A piano
4) A blackboard
5) In the dictionary entries

Tongue Twisters:

Say them aloud.

1. Troubles never troubled Trouble, as he himself troubled troubles.
   Mine collected fine and wished to have wine but the shopkeeper closed at nine for fear of fine.
   Bumble often mumbles something to Rumble but the latter does not catch the matter as nothing matters to him.
   Mr. Will, prepared a will as he willed to inherit his paper mill to his daughter, Jill.
   Ms. Sind wound the bandage round the wound and soon unwound it as it was not wound properly around the wound.

The Brave Little Bowman Summary

Once upon a time, there lived a skillful archer in a city. Though he was short in ‘ height and had a crooked back, none could beat him in archery. One day he thought, “I am good enough to join the king’s army, but he would never take ine in because of my short stature and hunched back. I must look for someone tall and powerful, and then I can enter the king’s army as his .page.”

One day, the little bowman found the kind of man he was looking for. He “was a tall and powerful man and used to dig ditches to earn his living. The bowman approached him and said, “The days of your misery are over! I am the best archer of this country and worthy of being a part of the king’s royal army. But, I may get rejected because of my height and crooked back. So, 1 need your help. You will immediately be recruited in the army because of your physique and you can then introduce me to them as your assistant. I will do the work that you will be given to do and we shall divide the pay between us. This way both of us will be able to live comfortably.”

The tall man gladly agreed. Together-they reached the king’s palace and sent word to the king that a famous bowman was there to meet him. The, king met the bowman and being impressed by his towering personality, joined him in the royal army. The little man’s dream had come true. He was now a part of the royal army, though disguised as the assistant of the big man.

In those days, there was a man-eater tiger on the loose in the jungle. The king sent for the big man and ordered him to kill the tiger. The big man told the little bowman what the king had said. They went to the forest together and soon, the little bowman shot the tiger dead. The king was extremely impressed by the heroic act of the big man and rewarded him with expensive gifts.

Some days, later, a wild elephant came on the city roads and started killing the people. The big man was asked to go and kill the elephant. The big man carried the little bowman on his shoulders and as always, the little bowman hit his target and killed the elephant. The king was full of praise for the big man and gave him a reward. The big man started treating the little man as his servant and spoke him very rudely. The little bowman was very sad.

A few days later, the king of the neighbouring country attacked the kingdom. The king at once &ent his army. The big man was mounted on a majestic elephant and was wearing shining armour. The little bowman knew that the big man could not shoot, so he also took his bow and arrow and quietly sat behind the big man on the elephant.

When the big man saw a huge enemy army in front of him, he started to shake with fear. The little bowman asked him to keep sitting quietly, but the big man was so nervous that he jumped off the elephant and ran back to the city from the battle-field.

The little bowman led the elephant fearlessly into the battle-field and killed many of the enemies with his unmistakable shots. All the soldiers were motivated by the little man’s act of bravery and they soon forced the enemy army to withdraw itself. The king now understood that it was the little bowman who was the read hero. He made him the chief of his army and also rewarded him with rich gifts.

Meanings For Difficult Worps

crooked (adj) : bent,or twisted out of shape
ditch (n) : a narrow channel dug at the side of the road or field, to carry away water
earn a living (idiom) : to earn money needed for food and clothing
praise (v) : express warm approval or admiration
harsh (adj) : unkind, severe
bowman (n) : an archer
Your Majesty! (phrase) : the title used to speak to a king (Respected great king)
Your Highness! (phrase) : the title used to speak to a king (Respected great king)
mounted (adj) : riding an animal, typically a horse
warrior (n) : a brave or experienced soldier or fighter
skilled (adj) : having or showing the knowledge or ability
panic (n) : sudden uncontrollable fear or anxiety
put fear to rest (phrase) : to calm one’s fear
gave a cold shoulder (phrase) : tread in an unfriendly way
a bolt from the blue (phrase) : a sudden unexpected news
armed (adj) : carrying weapons to fight

A Fairy Song Poem

Over hill, over dale,
Thorough bush, thorough brier,
Over park, over pale,
Thorough flood, thorough fire !
I do wander everywhere,
Swifter than the moon’s sphere;
And I serve the Fairy Queen,
To dew her orbs upon the green;
The cowslips tall her pensioners be;
In their gold coats spots you see;
Those be rubies, fairy favours;
In those freckles live their savours;
I must go seek some dewdrops here,
And hang a pearl in every cowslip’s ear. -By William Shakespeare

Appreciation of the Poem

A. Choose the correct options to complete the sentences.

1. The fairy wanders _________
a) over the dale
b) over the hill
c) everywhere
Answer:
c) everywhere

2. The fairy is serving the Fairy Queen by dropping upon the green.
a) dewdrops
b) cowslips
c) rubies
Answer:
a) dewdrops

3. The fairy walks faster than the rotation of the
a) Fairy Queen
b) dewdrops
c) Moon
Answer:
c) Moon

4. The fairy wants to hang a in every cowslip’s ear.
a) dewdrops
b) ruby
c) pearl
Answer:
c) pearl

5. Who are the fairy queen’s pensioners?
a) cowslips
b) dew drops
c) orbs
Answer:
a) cowslips

B. Answer the following questions :

1. Where does the fairy wander?
Answer:
The fairy wanders over hills, dales, parks and pales and through bushes, briers, floods and fire.

2. How quickly does the fairy wander?
Answer:
He wanders faster than the moon.

3. Who does the fairy serve?
Answer:
The fairy serves the Fairy Queen.

4. What are the spots on the cowslips compared with ?
Answer:
The sports on the cowslips are compared with rubies.

5. Identify and write the other rhyming words in the poem:.
( E.g. dale – pale)
Answer:
brier – fire where – sphere
queen – green be – see
favours – savours here- ear

Check Point

A Fairy Song Summary

The poem ‘A Fairy Song’, refers to a fairy that serves his/her fairy queen. He/She spreads the dew on the flower everywhere he/she crosses. He/She wanders many places to do this work like hills, pales and so on.

The fairy flies over hill and open river valleys, through bushes and prickly plants, above parks and fences, through floods and fire.

The fairy travels everywhere faster than the moon revolves around the earth. The fairy serves the Fairy Queen.

The fairy works for the fairy queen and must deliver dewdrops (orbs here refers to the spherical shape of the drops) on the greenery around. This includes delivering dewdrops to the cowslips – a yellow flower with tall slender stems. The cowslips are therefore indebted to the fairy queen and therefore become her pensioners.

In their yellow gold petals being referred to as coats… thus personifying it in a way, you can see spots. The spots are red in colour and therefore look like rubies. If you have seen a cowslip, you will notice it has red spots in the centre. The poet says this is possible because of the favour the fairy does to the cowslips by delivering dew to them. The red spots are compared to freckles that appear at the peak of a cowslip’s life.

The fairy finally says that he/she must look for more dewdrops that have been compared to pearls so that he/she can hang them in every cowslip’s ear. Again this is a personification where the cowslip is given a human quality of having an ear that can be fashioned with a pearl.

A Fairy Song About the Poet

William Shakespeare (1564 – 1616) was an English playwright, poet, and actor often called the English National Poet and consid¬ered by many to be the greatest dramatist of all time. He was nicknamed The Bard of Avon. Shakespeare’s works include 38 plays, 2 narrative poems, and 154 sonnets and a variety of other poems. His plays like Hamlet, Macbeth, King Lear are some of the finest works in those genres. Some of his works are studied as academic subjects at postgraduate level across the world. This poem (A Fairy Song) is

Meanings For Difficult Words

dale (n) : an open river valley (in a hilly area)
thorough (prep.) : old spelling of ‘through’
brier (n) : tangled mass of prickly plants / a thorny plant
pale (n) : a wooden strip forming part of a fence
wander (v) : move about aimlessly or without any destination, often in search of food or employment
swifter (adj) : faster
sphere (n) : range / ball / area
to dew her orbs (phr.) : In this poem, dew has been used as a verb which could mean to place ‘tiny drops (orbs) of water that form on cool surfaces at night, when atmospheric vapor condenses’
cowslips (n) : The cowslip is a yellow flower belonging to the primrose family. Its name comes from old English for cow dung, perhaps because the plant commonly grew amongst the manure in cow pastures.
pensioners (n) : followers/dependants
rubies (n) : red gemstones
favours (v) : to treat somebody better than you treat other people
freckles (n) : a small brownish spots (of the pigment melanin) on the skin
savours (v) : get enjoyment from; take pleasure in
dewdrops (n) : drops of dew

Language Devices in the Poem :
Hyperbole : Line 4 & Line 6
→ Thorough flood, thorough fire!
→ Swifter than the moon’s sphere

Personification : Line 14
And hang a pearl in every cowslip’s ear
Simile : Line 6

The writer uses connective word ‘than’ in this line. The poet is comparing ‘swifter’ to the moon’s sphere.
→ Swifter than the moon’s sphere

SCERT AP 10th Class Maths Textbook Solutions Chapter 8 సరూప త్రిభుజాలు Exercise 8.3 Textbook Exercise Questions and Answers.

AP State Syllabus 10th Class Maths Solutions 8th Lesson సరూప త్రిభుజాలు Exercise 8.3

ప్రశ్న 1.
ఒక లంబకోణ త్రిభుజము మూడు భుజాలపై సమబాహు త్రిభుజాలు గీయబడ్డాయి. కర్ణము మీద గీసిన త్రిభుజ వైశాల్యము మిగిలిన రెండు భుజాల మీద గీసిన త్రిభుజాల వైశాల్యాల మొత్తమునకు సమానమని చూపండి.
సాధన.

దత్తాంశము :
∆ABC లంబకోణ త్రిభుజం
∠B = 90°.
∆ABP, ∆AQC, ∆BCRల సమబాహు త్రిభుజాలు.

సారాంశము :
∆AQC వైశాల్యం = ∆APB వైశాల్యం + ∆BCR వైశాల్యం

నిరూపణ :
∆ABP ~ ∆BCR ~ ∆ACR (∵ సమబాహు త్రిభుజాలు ఎల్లప్పుడు సరూపాలు)

(∵ సరూప త్రిభుజాల వైశాల్యాల నిష్పత్తి వాని అనురూప భుజాల వర్గాల నిష్పత్తికి సమానం)

(పైథాగరస్ సిద్ధాంతం నుండి)

∴ ∆ACQ వైశాల్యం = ∆ ABP వైశాల్యం + ∆ BCR వైశాల్యం.

ప్రశ్న 2.
ఒక చతురస్రము భుజముపై గీచిన సమబాహు త్రిభుజ వైశాల్యము, ఆ చతురస్ర కర్ణముపై గీచిన సమబాహు త్రిభుజ వైశాల్యములో సగము వుంటుందని చూపండి.
సాధన.

దత్తాంశము :
ABCD ఒక చతురస్రము ∆ABP మరియు ACQలు వరుసగా చతురస్ర భుజం, కర్ణాల మీద గీచిన సమబాహు త్రిభుజాలు.
సారాంశము :
∆ABP వైశాల్యం = \(\frac{1}{2}\) ∆ACQ వైశాల్యం
నిరూపణ :

[∵ ∆ABP ~ ∆ACQ]
(∵ సరూప త్రిభుజాల వైశాల్యాల నిష్పత్తి వాని అనురూప భుజాల వర్గాల నిష్పత్తికి సమానం)

= \(\frac{\mathrm{AB}^{2}}{(\sqrt{2} \mathrm{AB})^{2}}\) [ABCD చతుర్భుజంలో]

= \(\frac{A B^{2}}{2 A B^{2}}=\frac{1}{2}\) [AC = √2 AB]

∴ ∆ABP వైశాల్యం = \(\frac{1}{2}\) ∆ACQ వైశాల్యం.

ప్రశ్న 3.
∆ ABCలో BC, CA, AB భుజాల మధ్య బిందువులు వరుసగా D, E, F. అయిన ∆DER మరియు ∆ABC ల వైశాల్యాల నిష్పత్తిని కనుగొనండి.
సాధన.

దత్తాంశము :
∆ABCలో; D, E మరియు , F లు BC, CA మరియు AB భుజాల మధ్య బిందువులు. ∆ABCలో AB, ACల మధ్య బిందువులను కలుపగా EF ఏర్పడినది.
FE || BC కావున \(\frac{A F}{F B}=\frac{A E}{E C}\)
(ప్రాథమిక అనుపాత సిద్ధాంత విపర్యయము నుండి)
అదే విధముగా AC మరియు BC లను DE ఒకే నిష్పత్తిలో విభజిస్తుంది. కావున DE || AB.
□BDEFలో ఎదుటి భుజాలు సమాంతరాలు (BD || EF మరియు DE || BF)
కావున OBDEF ఒక సమాంతర చతుర్భుజము ఇక్కడ DF ఒక కర్ణము.
∴ ∆BDF = ∆DEF ………… (1)
అదే విధముగా ∆DEF = ∆CDE అని నిరూపించవచ్చును. ………… (2) [∵ CDEF ఒక సమాంతర చతుర్భుజం] మరియు
∆DEF = ∆AEF …………. (3) [∵ □AEDF ఒక సమాంతర చతుర్భుజం]
(1), (2) మరియు (3) ల నుండి
∆AEF ≈ ∆DEF ≈ ∆BDF ≈ ∆CDE
అదే విధముగా ,
∆ABC = ∆AEF + ∆DEF + ∆BDF + ∆CDE = 4. ∆DEF
∆ABC : ∆DEF = 4 : 1.

ప్రశ్న 4.
∆ABCలో, XY || AC మరియు XYఆ త్రిభుజాన్ని రెండు సమాన వైశాల్యాలు గల భాగాలుగా AX విభజించును. అయిన \(\frac{\mathrm{AX}}{\mathrm{XB}}\) నిష్పత్తిని కనుగొనండి.
సాధన.

దత్తాంశము :
∆ABC లో XY | | AC.
సారాంశము :
\(\frac{\mathrm{AX}}{\mathrm{XB}}\) నిష్పత్తి , XY, ∆ABC ను సమాన వైశాల్యాలు గల భాగాలుగా విభజించును. ∆ABC, ∆XBY లలో ∠B = ∠B
∠A = ∠X [∵ XY || AC; ∠A, ∠X మరియు ∠C, ∠Yలు ఆసన్నకోణాల జత]
∆ABC ~ ∆XBY (కో.కో.కో సరూపకత ధర్మము ప్రకారము)
ఆ విధముగా \(\frac{\Delta \mathrm{ABC}}{\Delta \mathrm{XBY}}=\frac{\mathrm{AB}^{2}}{\mathrm{XB}^{2}}\)
[∵ రెండు సరూప త్రిభుజాల వైశాల్యాల నిష్పత్తి వాటి అనురూప భుజాల నిష్పత్తి వర్గమునకు సమానము)
\(\frac{2}{1}=\frac{\mathrm{AB}^{2}}{\mathrm{XB}^{2}}\)
[దత్తాంశంలో ∆BXY = ∆BAC కావున ∴ ∆ABC = 2 . ∆XBY]
2 = \(\left(\frac{\mathrm{AB}}{\mathrm{XB}}\right)^{2}\)

2 = \(\left(\frac{\mathrm{AX}+\mathrm{XB}}{\mathrm{XB}}\right)^{2}\)

2 = \(\left(\frac{\mathrm{AX}}{\mathrm{XB}}+\frac{\mathrm{XB}}{\mathrm{XB}^{\prime}}\right)^{2}\)

2 = \(\left(\frac{\mathrm{AX}}{\mathrm{XB}}+1\right)^{2}\)

⇒ \(\frac{\mathrm{AX}}{\mathrm{XB}}\) + 1 = √2

⇒ \(\frac{\mathrm{AX}}{\mathrm{XB}}\) = √2 – 1
కావున ఆ నిష్పత్తి \(\frac{\mathrm{AX}}{\mathrm{XB}}=\frac{\sqrt{2}-1}{1}\).

ప్రశ్న 5.
రెండు సరూపత్రిభుజాల వైశాల్యాల నిష్పత్తి వాటి – అనురూప మధ్యగతాల నిష్పత్తి వర్గానికి సమానమని చూపండి.
సాధన.

దత్తాంశము : ∆ABC ~ ∆XYZ
సారాంశము : \(\frac{\Delta \mathrm{ABC}}{\Delta \mathrm{XYZ}}=\frac{\mathrm{AD}^{2}}{\mathrm{XW}^{2}}\)
ఉపపత్తి : రెండు సరూప త్రిభుజాల వైశాల్యాల నిష్పత్తి వాటి అనురూప భుజాల నిష్పత్తి వర్గమునకు సమానము.
\(\frac{\Delta \mathrm{ABC}}{\Delta \mathrm{XYZ}}=\frac{\mathrm{AD}^{2}}{\mathrm{XW}^{2}}\) …………..(1) [∵ ∆ABC ~ ∆XYZ]
∆ABD మరియు ∆XYW లలో ∠B = ∠Y; ∠D = ∠W = 90°
(కో.కో.కో ఉప సిద్ధాంతము నుండి),
∆ABD ~ ∆XYW
∴ \(\frac{\Delta \mathrm{ABD}}{\Delta \mathrm{XYW}}=\frac{\mathrm{AB}^{2}}{\mathrm{XY}^{2}}=\frac{\mathrm{AD}^{2}}{\mathrm{XW}^{2}}\) …………..(2)
(1) మరియు (2) ల నుండి,
\(\frac{\Delta \mathrm{ABC}}{\Delta \mathrm{XYZ}}=\frac{\mathrm{AD}^{2}}{\mathrm{XW}^{2}}\)
ఆ విధముగా రెండు సరూప త్రిభుజాల వైశాల్యాల నిష్పత్తి వాటి అనురూప భుజాల నిష్పత్తి వర్గమునకు సమానము.

ప్రశ్న 6.
∆ABC ~ ∆DEF. BC = 3 సెం.మీ, EF = 4 సెం.మీ, ∆ABC వైశాల్యము = 54 చ.సెం.మీ అయిన ∆DEF వైశాల్యమును కనుగొనుము.
సాధన.

దత్తాంశము ప్రకారం, ∆ABC ~ ∆DEF.
BC = 3 సెం.మీ.; EF = 4 సెం.మీ. ∆ABC = 54 చ.సెం.మీ
∴ ∆ABC ~ DEF, కావున \(\frac{\Delta \mathrm{ABC}}{\Delta \mathrm{DEF}}=\frac{\mathrm{BC}^{2}}{\mathrm{EF}^{2}}\)
[∵ సరూప త్రిభుజాల వైశాల్యాల నిష్పత్తి. వాటి అనురూప భుజాల వర్గ నిష్పత్తికి సమానము].
\(\frac{54}{\Delta \mathrm{DEF}}=\frac{3^{2}}{4^{2}}\)
∴ ∆DEF = \(\frac{54 \times 16}{9}\) = 96 సెం.మీ.

ప్రశ్న 7.
త్రిభుజము ABCలో AB భుజాన్ని P వద్ద, AC ని Q వద్ద తాకునట్లు PQ ఒక సరళరేఖ, ఇంకా AP = 1 సెం.మీ., BP = 3 సెం.మీ. AQ = 1.5 సెం.మీ., CQ = 4.5 సెం.మీ. అయిన ∆APQ వైశాల్యము = \(\frac{1}{16}\) (∆ABC వైశాల్యము) అని చూపండి.
సాధన.

దత్తాంశము ప్రకారం, ∆ABC మరియు \(\overline{\mathrm{PQ}}\), AB ను P వద్ద మరియు AC ను Q వద్ద ఖండించుచున్నది.
AP = 1 సెం.మీ; AQ = 1.5 సెం.మీ BP = 3 సెం.మీ; CQ = 4.5 సెం.మీ
\(\frac{\mathrm{AP}}{\mathrm{BP}}=\frac{1}{3}\) ……………. (1);
\(\frac{\mathrm{AQ}}{\mathrm{QC}}=\frac{1.5}{4.5}=\frac{1}{3}\) ……………(2)
(1) మరియు (2) ల నుండి \(\frac{\mathrm{AP}}{\mathrm{BP}}=\frac{\mathrm{AQ}}{\mathrm{CQ}}\)
[∵ PQ, AB మరియు AC లను ఒకే నిష్పత్తిలో విభజించింది]
ప్రాథమిక అనుపాత సిద్దాంత విపర్యయము నుండి PQ || BC.
∆APQ మరియు ∆ABC లలో
∠A = ∠A (ఉమ్మడి కోణం)
∠P = ∠B [∵ PQ || BC సమాంతరరేఖల అనురూప కోణాలు] .
∠Q = ∠C
∴ ∆APQ ~ ∆ABC [∵ కో.కో.కో సరూప నియమము నుండి]
\(\frac{\Delta \mathrm{APQ}}{\Delta \mathrm{ABC}}=\frac{\mathrm{AP}^{2}}{\mathrm{AB}^{2}}\)
[∵సరూప త్రిభుజాల వైశాల్యాల ‘నిష్పత్తి వాటి అనురూప భుజాల వర్గాల నిష్పత్తికి సమానము].
= \(\frac{1^{2}}{(3+1)^{2}}=\frac{1}{16}\)
∴ ∆APQ = \(\frac{1}{16}\) (∆ABC) నిరూపించబడినది.

ప్రశ్న 8.
రెండు సరూప త్రిభుజాల వైశాల్యాలు 81 చ.సెం.మీ మరియు 49 చ.సెం.మీ. పెద్ద త్రిభుజములో గీసిన లంబము పొడవు 4.5 సెం.మీ అయిన చిన్న త్రిభుజములో దాని అనురూప లంబము పొడవును కనుగొనండి. .
సాధన.

దత్తాంశము : ∆ABC ~ ∆DEF ∆ABC = 81 సెం.మీ²; ∆DEF = 49 సెం.మీ²; AX = 4.5 సెం.మీ
సారాంశము : DY పొడవు
ఉపపత్తి : \(\frac{\Delta \mathrm{ABC}}{\Delta \mathrm{DEF}}=\frac{\mathrm{AX}^{2}}{\mathrm{DY}^{2}}\)
[∵ రెండు సరూప త్రిభుజాల వైశాల్యాల నిష్పత్తి వాటి అనురూప భుజాల వర్గాల నిష్పత్తికి సమానము]
\(\frac{81}{49}=\frac{(4.5)^{2}}{D Y^{2}}\)

⇒ \(\left(\frac{9}{7}\right)^{2}=\left(\frac{4.5}{D Y}\right)^{2}\)

⇒ \(\frac{9}{7}=\frac{4.5}{\mathrm{DY}}\)

⇒ DY = 4.5 × \(\frac{7}{9}\)

∴ DY = \(\frac{7}{2}\) = 3.5 సెం.మీ.