Physics Test 24

Total Questions: 26

1 - Method of transfer of heat is/are

A ) 1
B ) 2
C ) 3 ✅
D ) 4

2 - Metals are good .............. of heat.

A ) Conductor ✅
B ) insulator
C ) Semiconductor
D ) Non conductor

3 - Substance through which heat does not pass casily are called

A ) Conductor
B ) lnsulator ✅
C ) Semiconductor
D ) Both a & b

4 - Wood, cork, cotton, glass and rubber are........ substance.

A ) . conductor
B ) lnsulator ✅
C ) Semiconductor
D ) B

5 - The formula of rate of flow of heat is

A ) Q/t ✅
B ) Q×t
C ) Q+t
D ) Q×T

6 - Unit of rate of flow of heat is

A ) Js
B ) J-¹
C ) S-¹
D ) Js-¹ ✅

7 - Rate of flow of heat in solid object depends upon ____

A ) Area of the solid
B ) Length of solid
C ) Temp. difference
D ) All of these

8 - The unit of thermal conductivity is

A ) Js-¹m-¹K-¹
B ) Wm-¹ K-¹
C ) Both a and b
D ) JKg-¹ K-²

9 - Thermal conductivity of air is

A ) 0.59 Wm-¹ K-¹
B ) 0.08 Wm-¹ K-¹
C ) 0.026 Wm-¹ K-¹ ✅
D ) 0.6 Wm-¹ K-¹

10 - ____ has the minimum thermal conductivity is

A ) Rubber
B ) Air ✅
C ) Wood
D ) Water

11 - ____hes the maximum thermal conductivity is

A ) Aluminium
B ) Copper ✅
C ) Silver
D ) Brass

12 - Water is a____conductor of heat.

A ) Good
B ) Bad ✅
C ) Better
D ) None of these

13 - State of matter are ____

A ) Liquids
B ) Gases
C ) Solids
D ) All of these

14 - Air is ____ on heating.

A ) Dense
B ) Rare ✅
C ) Solid
D ) Steam

15 - Transfer of heat by actual movement of molecules from hot place to cold place is called

A ) Conduction ✅
B ) Convection
C ) Radiation
D ) Absorption

16 - Due to difference in densities of air in atmosphere make ____

A ) Convectional current ✅
B ) Cold welds
C ) Radiation
D ) Absorption

17 - Land and sea breeze is the result of ___

A ) Radiation
B ) Conduction
C ) Convection current ✅
D ) Thermal conductivity

18 - At night the air blow from earth to sea called

A ) Land breeze ✅
B ) Sea breeze
C ) Both a and b
D ) None

19 - In the day the air below from sea to eart called

A ) Land breeze
B ) Sea breeze ✅
C ) Both a and b
D ) None

20 - What causes a glider to remain in air?

A ) Radiation
B ) Conduction
C ) Convection current ✅
D ) Thermal conductivity

21 - Transfer of heat by waves the methods is called.

A ) Conduction
B ) Convection
C ) Radiation ✅
D ) None

22 - Transfer of heat by radiation depends upon.

A ) Colour and structure of surface
B ) Temperature of surface
C ) Area of surface
D ) All of these

24 - Which of the following surfaces is better emitter?

A ) A dull black surface ✅
B ) White surface
C ) A silvered surface
D ) None

25 - Which of the following surfaces is better reflected?

A ) A dull black surface
B ) White surface
C ) A silvered surface ✅
D ) None

26 - Convection of heat is the process of heat transfer due to the

A ) Random motion of molecules
B ) Upward motion of molecules ✅
C ) Downward movement of molecules
D ) Free motion of molecules