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## Homework Statement

A crate is pulled up a rough incline. The pulling force is parallel to the incline. The crate is pulled a distance of 5.79 m. The acceleration of gravity is 9.8 m/s^2

theta=23.4 degrees

mass= 8.91kg

Force pulling on box= 142N

coefficient of friction= 0.292

Initial velocity of box= 1.48m/s

A.What is the magnitude of the work is done by the gravitational force? Answer in units of J.

B.How much work is done by the 142 N force? Answer in units of J.

## Homework Equations

PE= mgh

W=F*displacement*cos(theta)

## The Attempt at a Solution

A. I tried using the mgh formula but height is not given. Then, I tried the second formula given but I do not know how to calculate the displacement.

B. Used the second equation got W= 142N*5.79*cos(23.4). Ended up being incorrect.

UPDATE: got the second one as the cos(theta) ended up being 1 as the angle between the displacement and the force was 0.

Clearly lost. I do not know where to properly start so a hint at that would be helpful![/B]

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