1. What is Heat Topic 4.2 cont.

2. Joule’s Mechanical Equivalent of Heat Joule determined the amount of work (ENERGY) done on the water in his apparatus and related it to the change in temperature of the water.

3. He calculated 4.16 J causes an increase of 1.0 o C

4. The true value with modern equipment is 4.186 J Joule was off by less than 1%! Pretty ingenious!

5. Joule defined the calorie: 1 calorie = the amount of energy needed to raise 1 g H 2 O 1 o C

6. 1 st Law of Thermodynamics

7. ENERGY CANNOT BE CREATED OR DESTROYED, BUT IT CAN BE CONVERTED FROM ONE FORM TO ANOTHER MRS CHEN

8. WHAT IS HEAT?

9. KINETIC-MOLECULAR THEORY OF HEAT Hint: kinetic means motion!

10. Heat = THERMAL ENERGY Heat = transfer of thermal energy from one object to another

11. Specific Heat Capacity

12. Heat = total kinetic energy of all the molecules in a substance Temperature = average kinetic energy of all the molecules in a substance

13. Put your thinking cap on! True or false? A cup of soup and a huge bowl of soup from a big pot of soup have the same temperature.

14. Hint: what do you use to measure temperature?

15. Put your thinking cap on! Which one has the most thermal energy (heat)?

16. Hint: if you were freezing cold which one would you like to stand next to?

17. 2 nd Law of Thermodynamics No process can be 100% efficient. Some energy will always be lost as heat (friction)

18. Assignment: Read Topic 4.3 and finish your notes. Review for you Ch 4 test: Checklist and vocab On line Science Focus tests for Chapter 4 Practice Test – online – write down answers, correct and hand in with your vocab and checklist.