A 35-N bucket of water is lifted vertically 3.0 m and then returned to its original position. How much work did gravity do on the bucket during this process?

W = 105 J

Explanation:

Given: F = 35 N, D = 3.0 m

W=?

Sol:

Work done = Force * distance

W = 35 N * 3 = 105 J

0 J

Explanation:

From the question, let us assume that a positive work was done in lifting the bucket down and a negative work was done in lifting the bucket up.

Going up

W = - Fd ... Equation 1

Where W = work done, F = Force needed to lift the bucket, d = distance

Given: F = 35 N, d = 3.0 m

Substitute into equation 1

F = - 35 (3.0)

F = - 105 N.

Coming Down

W = Fd

Given: F = 35 N, d = 3.0 m

W = 35 (3.0)

W = 105 N.

During the process (going up and coming down)

ΔW = - 150+105

ΔW = 0 J

Hence the work done by gravity during the process = 0 J