Physics
A body is moved in a direction opposite to the direction of force acting on it. State whether the work is done by the force or work is done against the force.
Work, Energy & Power
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Answer
When a body is moved in a direction opposite to the direction of force then work is done against the force acting on the body.
When the displacement of the body due to application of force is in a direction opposite to the force then,
θ = 180°, and
cos 180° = -1
Therefore, Work done = (-) Force x displacement of the body.
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