AP Board 7th Class Science Notes Chapter 5 Temperature and Its Measurement

Students can go through AP State Board 7th Class Science Notes Chapter 5 Temperature and Its Measurement to understand and remember the concept easily.

AP State Board Syllabus 7th Class Science Notes Chapter 5 Temperature and Its Measurement

→ Temperature is a measure of the degree of hotness or coldness of an object.

→ Heat is a form of energy.

→ The energy which makes an object appear hot or cold is called heat.

→ If we use the electrical heater to heat water electrical energy is converted to heat.

→ In solar heaters, solar energy is converted to heat.

→ All thermometers are based on the fact that matter expands on heating.

→ Mercury is a good conductor of heat.

→ Mercury is available in a pure state.

→ The first thermometer was invented by Galileo in 1593 A.D.

→ The normal temperature of the human body is 37 °C (98.6 °F)

→ The average body temperature of a large number of healthy persons is known as normal temperature.

→ Thermister thermometer is used to measure the temperature for infants and children.

→ Temperature is the degree of hotness or coldness of an object.

→ Heat flows from an object at a high temperature to another at a lower temperature.

→ Mercury and alcohol are used as thermometer liquids in thermometer.

→ Doctors use a clinical thermometer to measure the human body temperature.

→ A Laboratory thermometer is used to measure the temperature of objects.

→ Heat energy: A form of energy that is transferred by a difference in temperature
→ Temperature: The degree of hotness or coldness of a body or environment.

→ Thermometer: An instrument for measuring temperature, especially one having a graduated glass tube with a bulb containing a liquid, typically mercury or coloured alcohol, that expands and rises in the tube as the temperature increases.

→ Fahrenheit scale: A temperature scale that defines the freezing point of water as 32 degrees and the boiling point of water a 212 degrees.

→ Celsius scale: A scale of temperature in which 0° represents the melting point of ice and 100 represents the boiling point of water.

→ Clinical thermometer: A thermometer is used to measure body temperature, especially a small glass thermometer designed with a narrowing above the bulb so that the mercury column stays in position when the instrument is removed from the body.

→ Expansion: An increase in the volume of a substance while its mass remains the same. Expansion ¡s usually due to heating. When substances are heated, the molecular bonds between their particles are weakened, and the particles move faster, causing the substance to expand.

→ Kink: A tight curl, twist, or bend in a length of thin material, as one caused by the tensing of a looped section of wire.

→ Jerk: To give a sudden quick thrust, push, pull, or twist to.

→ Lukewarm: Minimum level of temperature.

→ Vessel: A hollow utensil, such as a cup, vase, or pitcher used as a container, especially for liquids

→ Solar heater: A heater that makes direct use of solar energy.

→ Solar energy: The radiant energy emitted by the Sun Energy is derived from the Sun’s radiation. Passive solar energy can be exploited through architectural design, by positioning windows to allow sunlight to enter and help heat a space. Active solar energy involves the conversion of sunlight to electrical energy, especially in solar (photovoltaic).

→ Radiant energy: Energy transferred by radiation, especially by an electromagnetic wave.

→ In Libya (Africa) on a particular day in the year 1922, ¡t became so hot that the temperature of air even in shade was a high as 58°C. At some places (Rentachirnala of Guntur district) in Andhra Pradesh, the maximum temperature of air sometimes reaches 48°C and more. When it is so hot we feel extremely uncomfortable as the normal temperature of the human body is 37°C. The lowest temperature In the world has been measured ¡n Antarctica where it once went down to about -89°C.

The minus sign is used for temperature which s less than 0°C. Water freezes at 0°C, just think how cold-89°C must be. In winter when the atmospheric temperature around us becomes 15°C – 20°C we begin to feel cold.

→ C V. Raman:
C V. Raman is Chandra Sekhar Venkata Raman. He was the first Indian Scientist to become Sir C V Raman. He won the Nobel Prize iii Physics in 1930. His work is on the scattering of light’ His discovery ‘effect of light rays named after him as ‘Ruinan effect’. Ruman was born on 7th November 1888 in Thiruchunapalli TamilNadu. During a sea-voyage in 1921, Raman became anxious to know; why sea-water, sky and glaciers were blue in colour. He finally brought forth the reason for the blue colour of the sky, sea-water and glaciers. He announced the Raman effect on February 28 and so that day is observed as the National Science Day. This Nobel scientist died on 20th November 1970.