Question

KE and PE Math

Directions: Consider a 2-kg bowling ball sits on top of a building that is 40 meters tall. It falls to the ground. Think about the amounts of potential and kinetic energy the bowling ball has:
as it sits on top of a building that is 40 meters tall.
as it is half way through a fall off a building that is 40 meters tall and travelling 19.8 meters per second.
as it is just about to hit the ground from a fall off a building that is 40 meters tall and travelling 28 meters per second.

Questions

1. Does the bowling ball have more potential energy or kinetic energy as it sit on top of the building? Why?

2. Does the bowling ball have more potential energy or kinetic energy as it is half way through its fall? Why?

3. Does the bowling ball have more potential energy or kinetic energy just before it hits the ground? Why?

4. What is the potential energy of the bowling ball as it sits on top of the building?

5. What is the potential energy of the ball as it is half way through the fall, 20 meters high?

6. What is the kinetic energy of the ball as it is half way through the fall?

What is the kinetic energy of the ball just before it hits the ground?

Answer 1

The person above has everything, except for 2 I put " kinetic energy since it is in motion, and is picking up speed. It has already used up all of the potential energy " I don't think the potential energy and kinetic energy is equal

Step-by-step explanation:

Answer 2

1. Answer: The bowling ball has more potential energy as it sits on top of the building. It does not have any kinetic energy because it is not moving.

2. Answer: The bowling ball has equal amounts of potential and kinetic energy half way through the fall. At the half way point, half of the potential energy has been converted to kinetic energy.

3. Answer: Just before the ball hits the ground, it has more kinetic energy. As it hits the ground the potential energy becomes zero.

4. Answer:

PE=784 J

5. Answer:

PE = 392 J

6. Answer:

KE= 392 J

Also, since the PE and KE are equal at the half way point and PE =392 J, KE = 392 J.

7. What is the kinetic energy of the ball just before it hits the ground?

Answer:

KE=784 J

At first I answered in the comments, but I am able to answer now. I hope this can help