Question

name____ period:____
kinetic and potential energy
directions part 1: use the graph below that shows a ball rolling from point a to point g to answer the following questions.

1. which letter shows the ball when it has maximum kinetic energy?______
2. which letter shows the ball when it has maximum potential energy?______
3. which letter shows the ball when it has the least kinetic energy?______
4. which letter shows the ball when it has the least potential energy?______
5. which letter shows the ball when it has just a little more kinetic energy than a?______
6. which letter shows the ball when it has just a little more potential energy than c?______
7. which letter shows the ball when it has just a little less potential energy than f?______
8. which letter shows the ball when it has just a little more kinetic energy than g?______
9. which letter shows the ball when it has just a little less kinetic energy than d?______
10. which letter shows the ball when it has just a little less potential energy than c?______
11. which letter shows the ball when it has the most mechanical energy?______
12. which sequence correctly shows an increase in potential energy?

a. e, f, b, g c. b, f, e, c
b. d, e, b, f d. a, g, f, c

Explanation:

Step1: Recall energy - height relationship

Kinetic energy is maximum at the lowest - point as speed is maximum there, and potential energy is maximum at the highest - point as height is maximum.

Step2: Analyze each question

1. The ball has maximum kinetic energy at the lowest point. Point D is the lowest point, so the answer is D.
2. The ball has maximum potential energy at the highest point. Points A and G are the highest points, so the answer is A, G.
3. The least kinetic energy is at the highest points (where speed is zero). Points A and G are the highest points, so the answer is A, G.
4. The least potential energy is at the lowest point. Point D is the lowest point, so the answer is D.
5. A little more kinetic energy than A means a point slightly lower than A. Point B is slightly lower than A, so the answer is B.
6. A little more potential energy than C means a point slightly higher than C. Point B is slightly higher than C, so the answer is B.
7. A little less potential energy than F means a point slightly lower than F. Point E is slightly lower than F, so the answer is E.
8. A little more kinetic energy than G means a point slightly lower than G. Point F is slightly lower than G, so the answer is F.
9. A little less kinetic energy than D means a point slightly higher than D. Point E is slightly higher than D, so the answer is E.
10. A little less potential energy than C means a point slightly lower than C. Point D is slightly lower than C, so the answer is D.
11. In the absence of non - conservative forces, mechanical energy (sum of kinetic and potential energy) is conserved. So, it is the same at all points. But if we assume some small non - conservative forces (like air resistance), the initial state has the most mechanical energy. Points A and G are the starting points, so the answer is A, G.
12. Potential energy increases with height. Among the given sequences, D, E, B, F shows an increase in height and thus an increase in potential energy.

Answer:

1. D
2. A, G
3. A, G
4. D
5. B
6. B
7. E
8. F
9. E
10. D
11. A, G
12. b. D, E, B, F