Heat Transfer

1. Explain how a spoon dipped in hot water shortly gets hot at the free end?

Question 1 of 44

2. Black (dull) materials are better emitters of heat than white (shiny/polished) material?

Question 2 of 44

3. Define Lagging

Question 3 of 44

4. Which of the following is NOT a mode of heat transfer?

Question 4 of 44

5. Which of the following is not a property of the radiant heat from the sun?

Question 5 of 44

6. Rate of heat flow is inversely proportional to the length of a conductor. True or False?

Question 6 of 44

7. Which of the following is not among the factors affecting thermal conductivity?

Question 7 of 44

8. Metals are good conductors of heat?

Question 8 of 44

9. Convection currents move faster in

Question 9 of 44

10. Conduction can take place in liquid and gases?

Question 10 of 44

11. SI UNIT of heat is?

Question 11 of 44

12. When you heat water in a sufuria what happens?

Question 12 of 44

13. Thermal equilibrium is when 2 bodies at the same temperature are in contact and there is no heat flow?

Question 13 of 44

14. Rate of heat flow is directly proportional to cross-section area of a conductor. True or False?

Question 14 of 44

15. Convection is:

Question 15 of 44

16. Is the temperature difference between the ends of the conductor a factor affecting its thermal conductivity?

Question 16 of 44

17. Is water a poor conductor of heat?

Question 17 of 44

18. Name the two mechanisms of thermal conduction in metals

Question 18 of 44

19. Gases are the worst conductors of heat because of large inter-molecular distance?

Question 19 of 44

20. Non-metals are poor conductors of heat?

Question 20 of 44

21. Thermal conductivity depends on the nature of the material (metal) such as iron and copper?

Question 21 of 44

22. Explain reason why warm water in a heated sufuria rises and replaced by cold water from the top?

Question 22 of 44

23. Radiation is the flow of heat from one place to another by means of electromagnetic waves?

Question 23 of 44

24. Different metals have different thermal conductivities

Question 24 of 44

25. Which of the following is the main difference between metals and non-metals?

Question 25 of 44

26. DEFINE heat

Question 26 of 44

27. Which of the following describes an application of thermal radiation?

Question 27 of 44

28. Why are electrolytes better conductors of heat than pure liquid?

Question 28 of 44

29. Rate of heat flow increases or decreases according to the nature of material?

Question 29 of 44

30. Explain why steam pipes in industry are lagged with poor conductors of heat

Question 30 of 44

31. Black materials are better absorbers of heat than white material?

Question 31 of 44

32. Which of the following is not an application of convection in fluids

Question 32 of 44

33. What makes Radiation mode of heat transfer different from conduction and convection?

Question 33 of 44

34. What is the name given when you mix hot and cold parts of the fluid using external stirring such as fan or pump?

Question 34 of 44

35. Rate of heat flow is directly proportional to the temperature difference. True or False?

Question 35 of 44

36. Why are exhaust pipes in a ship covered with thick asbestos material?

Question 36 of 44

37. Which of one the following explains why Liquids are poor conductor of heat?

Question 37 of 44

38. A body emitting thermal radiation can also emit visible light when it is hot enough?

Question 38 of 44

39. How is heat transferred from the sun to the earth?

Question 39 of 44

40. Thermal conductivity increases as you increase in cross-section area of a material?

Question 40 of 44

41. Thermal conductivity increases as you decrease the length of a metal (material)?

Question 41 of 44

42. Explain why a copper rod gets hot earlier than an iron rod of the same shape and size and all put in the same heat source

Question 42 of 44

43. Conduction can take place in solids?

Question 43 of 44

44. Between a white car and a black car which one will absorb more heat than the other when you place both cars in an open field at 12 noon in Mombasa?

Question 44 of 44