Page 37 - Ripples SCIENCE 7 - TEJPUR Edition 2024 Answer Key

3. Heat is a form of ..................... .

(a) Matter (b) Energy (c) Fluid (d) None of these

Ans. (b)
4. The liquid used in a laboratory thermometer is ..................... .

(a) Mercury (b) Alcohol (c) Water (d) Kerosene
Ans. (a)

5. The SI unit of temperature is ..................... .

(a) Degree Celsius (b) Degree Fahrenheit
(c) kelvin (d) Metre

Ans. (c)
6. The process which can transfer heat through the vacuum, as well as air, is ............ .

(a) Conduction (b) Convection

(c) Irradiation (d) Radiation
Ans. (d)

7. An example of a conductor of heat is ..................... .

(a) Paper (b) Cloth (c) Air (d) Aluminium
Ans. (d)

8. A red hot metal ball is hanging from the roof with a metal chain. It is losing heat by:

(a) Conduction and radiation (b) Conduction and convection
(c) Convection and radiation (d) Conduction, convection and radiation

Ans. (a)
B. Fill in the blanks.

1. Copper is a ..................... conductor of heat.

Ans. good
2. The heat of the Sun comes to us through the process of ..................... .

Ans. radiation
3. Temperature is the ..................... of hotness or coldness.

Ans. degree

4. Liquids expand ..................... than gases.
Ans. slower

5. Heat transfers in solids through ..................... .

Ans. conduction
6. Three modes of transfer of heat are ....................., ..................... and ..................... .

Ans. conduction, convection and radiation

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