Suppose that you slowly lower a pail to the ground from a height of 1.5 meters above the ground. The pail weighs 100N. How much work is done by the force which you exert on the pail?

(A) 100Nm. (B) 150Nm.
(C) -100Nm. (D) -150Nm.


Questions --- What this question is about
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Suppose that you slowly lower a pail to the ground from a height of 1.5 meters above the ground. The pail weighs 100N. How much work is done by the force which you exert on the pail?

(A) 100Nm. --- No.

The force opposes the motion so the work done is negative.

Try again.
Questions --- What this question is about
19.3





































































Suppose that you slowly lower a pail to the ground from a height of 1.5 meters above the ground. The pail weighs 100N. How much work is done by the force which you exert on the pail?

(B) 150Nm. --- No.

The force opposes the motion so the work done is negative.

Try again.
Questions --- What this question is about
19.3





































































Suppose that you slowly lower a pail to the ground from a height of 1.5 meters above the ground. The pail weighs 100N. How much work is done by the force which you exert on the pail?

(C) -100Nm. --- No.

The work done is the force component multiplied by the distance.

Try again.
Questions --- What this question is about
19.3





































































Suppose that you slowly lower a pail to the ground from a height of 1.5 meters above the ground. The pail weighs 100N. How much work is done by the force which you exert on the pail?

(D) -150Nm. --- Yes.

The force component is - 100N so the work is
W = (-100N)(1.5m) = - 150 Nm.
Check the other answers.
Questions --- What this question is about
19.3