What is meant by work done by a force? When do we call work done to be positive or negative?

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What is meant by work done by a force? When do we call work done to be positive or negative? In a game of ‘tug of war’ state the type of work done by the winning and the losing teams


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Salim Ahmed Kawsar

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When force applied on a body causes the body to move then the work is said to be done by the force. 

Positive work done: when the body is displaced in the same direction that of the force then work done is positive. That is the angle between the force applied and displacement is 0o. 

Negative work done: when the body is displaced in the direction opposite to that of the force then work done is negative. Here the angle between the force applied and displacement is 180o. 

In the game of ‘tug of war’ work done by the winning team is positive and the work done by the losing team is negative.

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