# when is the work done by a force said to be negative? give one situation in which one of the forces acting on the object is doing positive and other is doing negative work.

When direction of displacement of the object is opposite to the applied force then the work done is said to be negative.

EXAMPLE - Work done in pulling a bucket of water from the well is positive work. Work done by gravitational force on a bucket of water being pulled upwards is negative work.

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when leela lifts a book, the force exerted by leela is in the direction of the movement of the book. thus,positive work is said to be done. whereas the gravitational force is opposite to the direction the book is moving.thus,negative work is said to be done.

another example of negative work is the working of a pulley.

example of positive work is climbing a tree.

negative work is said to be done when the force is opposite to the direction of displacement.

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The work done by the object is negative when the object moves in the opposite direction of the force.

the examle of positive work is as follows:

Let us consider an object standing at rest. For example someone used a force of 5N on the object. Then the object is displaced by 2m in the direction of the force. Therefore this is an example of positive work because the force is not in the opposite direction.

The example of negative force is as follows:

Let us consider a bicycle moving with the velocity "v"Then someone came and pulled it in the backward direction. So therefore this is an example of negative work as it is in the opposite direction.

Let an object be displaced in the oppos

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