Question

7. A 2kg ball is released from rest at the top of a track and reaches a speed of 10m/s at the bottom. a. How much kinetic energy does the ball have? b. how much potential energy did it have at the top of the hill (assuming no energy was lost)? c. What was the height of the hill?

Answer 1

Step-by-step explanation:

Kinetic energy formula:

KE = 1/2 m v^2

= 1/2 (2 kg)(10 m/s)^2 = 100 J of KE

This is equal to the Potential Energy that the ball HAD before it moved ...all of this PE was converted to the KE at the bottom....

PE = mgh = 100 J

2 kg * 9.81 m/s^2 * h = 100 j

h =5.1 m