Question

A 4 kg block is pushed up an incline that makes a 30o angle with the horizontal, as shown in the figure. Once the block is pushed a distance of d=5.0 m up the incline, the block remains at rest. What is the approximate change in the gravitational potential energy of the block-

Answer 1

Answer: 98 J

Step-by-step explanation:

The starting GPE is 0 because the block is at h=0 (bottom of the incline).

The block moves 5.0 m up the incline, so you have to figure out its height (h) relative to the bottom of the incline, where h=0.

sin30 = h/5

solve for h: h = sin30 x 5 = 2.5m (height of the block, 5 m up the incline)

Now you can solve for GPE = mgh

GPE = (4 kg)(9.8 m/s2)(2.5 m) = 98J