(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A 4.20 kg block is set into motion up an inclined plane with an initial speed of v0 = 7.70 m/s (Fig. P7.25). The block comes to rest after traveling 3.00 m along the plane, which is inclined at an angle of 30.0° to the horizontal.

1. For this motion, determine the change in the block's kinetic energy.

DeltaK = 1/2m(vf^2-vi^2)^2=-1/2mvi^2= -124.5J

This next question is the portion I am having problems with:

2. For this motion, determine the change in potential energy of the block-Earth system.

2. Relevant equations

DeltaU = mg(3.00)sin30.0

3. The attempt at a solution

=(4.20)(9.8)(3.00)(0.454)

=56.1

So what is wrong with my answer??

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# Homework Help: Change in Potential Energy: What am I doing wrong?

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