1. What is the general direction of the flow of thermal energy?

2. What is this flow of thermal energy called?

3. If you have two same sized glasses, one filled with water and the other half full of water, which one has the greater thermal energy?

4. For the two glasses of water in exercise 3, which one will require more energy to heat all of the water in the glass by 1 ^oC?

5. Using the equation for heat (Q = C_smT), if you wish to heat 100kg of water by 10 ⁰C in your bath, how much heat is needed (using the specific heat for water, Cs = 1000cal/1kg^oC)?

6. Which of these involves the least thermal energy: (a) 1 calorie, (b) 1 Calorie, or (c) 1 Joule?

7. If 200 Joules of heat is added to a system, and the system does 100 Joules of external work, how much is the thermal energy of the system raised?

8. Can an object be cooled to absolute zero temperature?

9. On which temperature scale does the average kinetic energy of molecules double when the temperature doubles?

10. Does temperature measure average kinetic energy or total kinetic energy?

11 What do you think would happen to the Earth's climate if the Greenhouse Effect did not happen (that it did not exist)?

12. What is it called when a solid changes directly into a gas?

13. How does the energy compare to heat water from 20 ^oC to 40 ^oC and to cool water from 40 ^oC to 20 ^oC?

14. For heat conductors, what is the role that electrons play?

15. If a barefoot firewalker walks on red-hot coals, why don't their feet burn?

16. Every object radiates heat (energy) to their surroundings, so why don't their temperatures decrease?

17. What are the four phases of matter?

18. What will heat your hand faster, touching a metal stove top coil at 100 ^oC or touching boiling water at 100 ^oC?

19. How much heat is needed to increase the temperature of 20g of water from 0 ^oC to 100 ^oC? (hint since the water remains in the liquid phase, you only need to know the heat needed from the specific heat equation Q = C_s mT, where C_s = 1cal/g^oC).

20. If you have 10g of 100 ^oC (boiling) water, how much heat is needed to turn it completely into steam (H₂O gas!)? (hint: since you are changing its phase from liquid to gas, you use the heat of vaporization equation, Q = m L_v, where L_v = 540 cal/g).