1. Warm up: what energy transformations are happening in the situations below? Activity 57: Conservation of Energy

2. Moving hands back and forth (kinetic energy) transforms into heat, or thermal energy. Activity 57: Conservation of Energy

3. At the top of a roller coaster, the car has the most potential energy. As it moves down the hill, the potential energy is transformed into kinetic energy. Activity 57: Conservation of Energy

4. What is the gravitational potential energy (GPE) formula? GPE= weight x height Calculating Gravitational Potential Energy

5. What has a greater GPE? ◦ A 30 gram bag of candy on a shelf that is 4 feet from the ground ◦ a 10 gram bag of candy that is 9 feet from the ground? Calculating Gravitational Potential Energy

6. GPE= w x h GPE= 30 x 4 GPE = 120 J GPE= w x h GPE= 10 x 9 GPE = 90 J

7. What has a greater GPE? ◦ a beaker weighing 40 grams sitting on a 5 foot tall shelf ◦ a 90 gram box sitting on a shelf 2 feet from the ground? Calculating Gravitational Potential Energy

8. GPE= w x h Calculating Gravitational Potential Energy GPE= 40 x 5 GPE = 200 J GPE= 90 x 2 GPE = 180 J

9. If a basketball has a GPE of 150 J and weighs 50 grams, how many feet is it from the ground? GPE= weight x height 150 J = 50 grams x height 150 J/50 grams= 3 feet Calculating Gravitational Potential Energy

10. How much does a Twix bar weigh (in grams) if its GPE is 120 J and it is placed on a shelf 5 feet from the ground? GPE = weight x height 120 J = weight x 5 feet 120 J/5 feet = 24 grams Calculating Gravitational Potential Energy

11. You and your partner will get a set of 9 cards. Using the clues, put the cards in order from least to greatest amount. You can only use a calculator, so no computers! GPE Puzzle GPE= ? Height= ?

12. Each person at your table will get on analysis question. You will have 5 minutes to answer the question given to you. Afterwards, you will present your answer to the group. Activity 56 Analysis Questions Jigsaw

13. Heat- the movement of thermal energy from hot to cold. Temperature- a measure of the average energy per molecule of a substance. Activity 56 In Case You Missed It…

14. The more amount of substance present, the more thermal energy it has. Activity 56 In Case You Missed It…

15. Energy can be transformed into different types. ◦ Potential can transform into kinetic. ◦ Kinetic can transform into thermal. Energy is transferred when it moves from one thing to another. ◦ The thermal energy created by shaking the shot transferred to the thermometer, giving us a temperature. Activity 56 In Case You Missed It…

16. Bill Nye explains how heat/thermal energy works. Bill Nye Bill Nye: Energy

17. Which of the following diagrams applies the Law of Conservation of Energy to a toaster in use? Activity 57: Conservation of Energy

18. Surprisingly, energy can be transferred or transformed but cannot be created, lost, or destroyed. The total amount of energy before something happens must equal the amount afterward. Law of Conservation of Energy

19. #4 on notes sheet asked what happens to “lost energy?” What are some common forms of “lost energy?” ◦ Sound ◦ Light ◦ Heat

20. #5: say you have a candle that has 15 J of chemical potential energy stored. When you light it, how many joules (J) should be transformed to light/thermal energy? Law of Conservation of Energy

21. Heat or thermal energy is almost always lost during energy transformations. ◦ #7: Why is heat or thermal energy hard to harness? Law of Conservation of Energy

22. Energy efficiency- the ratio of useful energy that is released to the total energy in the process. ◦ What is the efficiency of an engine that gives off 70% thermal energy? If 70% turns into thermal energy, the remaining 30% is what is used to power the engine. Energy Efficiency

23. Next class: quiz on Activities 53-57. ◦ Not open notebook. ◦ You may use one side of a 3x5 index card with notes. Activity 57 UC assessment (question #3 from the analysis questions) is due on Friday Jan. 15 th ◦ Scoring Guide in OneNote Tonight’s Homework