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#### Heat Model Question Paper

9th Standard

Reg.No. :
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Science

Time : 01:30:00 Hrs
Total Marks : 50
5 x 1 = 5
1. Calorie is the unit of

(a)

heat

(b)

work

(c)

temperature

(d)

food

2. The specific heat capacity of water is

(a)

4200 Jkg-1K-1

(b)

420 Jg-1K-1

(c)

0.42 Jg-1K-1

(d)

4.2 Jkg-1K-1

3. A device in which the loss of heat due to conduction, convection and radiation is minimized is

(a)

Solar cell

(b)

Solar cooker

(c)

Thermometer

(d)

4. The temperature at which a liquid gets converted into its vapour state is called its________

(a)

melting point

(b)

boiling point

(c)

dew point

(d)

freezing point

5. Which one of the following scales has lower fixed point at 0°C?

(a)

Kelvin scale

(b)

Fahrenheit scale

(c)

Celsius scale

(d)

All of these

6. 5 x 1 = 5
7. During day time, air blows from________________to_____________

()

sea to land

8. ___________is a process just reverse of melting

()

Freezing

9. _____________is the degree of hotness or coldness ofa body.

()

Temperature

10. ______________is greater for liquids than for solids and maximum in case of gases.

()

Expansion

11. Black marks appearing on the ceiling above a lamp or fan caused by dust being carried upwards in air __________ produced by hot lamp or the running fan.

()

convection currents

12. 5 x 1 = 5
13. Heat

14. (1)

4.2 J/g0C

15. m x s x t

16. (2)

Heat gained or lost when there is no change of state

17. Boiling point of water

18. (3)

336 J/g

19. Latent heat of fusion of ice

20. (4)

Form of energy

21. Specific heat capacity of water

22. (5)

1 millennium

4 x 2 = 8
23. What is the heat in joules required to raise the temperature of 25 grams of water from 0ºC to 100ºC? What is the heat in Calories?
(Specific heat of water = 4.18 J/gºC)

24. Define latent heat of fusion?

25. Define one calorie.

26. What is the minimum possible temperature? Is there also a maximum possible temperature?

27. 4 x 3 = 12
28. Define conduction

30. Define thermal capacity.

31. How much heat energy is required to melt 5 kg of ice? (Specic latent heat of ice = 336 Jg-1)

32. 3 x 5 = 15
33. Explain convection in daily life.

34. What are the changes of state in water? Explain.

35. Give the difference between heat and temperature.