A 3.0-kg cart rolls down a hill. Assume that the height of the cart changes from a maximum of 4.0 meters at the top of the hill to 0.0 meters at the bottom. The speed of the cart changes from 0.0 m/s to 3.0 m/s. How much kinetic energy does the cart have when it is half-way down the hill?

A) 6.0J

B) 12.0J

C) 58.8J

D) 117.6J

Question

Gibbs

Physics

19 February, 20:12

A 3.0-kg cart rolls down a hill. Assume that the height of the cart changes from a maximum of 4.0 meters at the top of the hill to 0.0 meters at the bottom. The speed of the cart changes from 0.0 m/s to 3.0 m/s. How much kinetic energy does the cart have when it is half-way down the hill?

A) 6.0J

B) 12.0J

C) 58.8J

D) 117.6J

+1

Answers (1)

Know the Answer?

Jamison Owens · Answer 1

C) 58.8 J

Explanation:

Initially, the cart has only potential energy.

PE = mgh

PE = (3.0 kg) (9.8 m/s²) (4.0 m)

PE = 117.6 J

Halfway down the hill, half the potential energy has been converted to kinetic energy.

KE = 117.6 J / 2

KE = 58.8 J