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Discuss the condition under which no work is done on a body.

No work is done on a body when the force applied to the body and the displacement of the body are perpendicular to each other.

In other words, when the angle (θ) between the force vector and the displacement vector is 90 degrees (θ = 90°), the cosine of 90 degrees is zero (cos(90°) = 0), which means the work done is zero. In the equation for work: W = F * d * cos(θ) When θ = 90°, cos(θ) = 0.

Therefore, the term cos(θ) becomes 0, and the work equation simplifies to: W = F ×d ×0 = 0 This means that if the force applied to a body is perpendicular to the direction of its displacement, no work is done on the body.

The force may be exerted on the body, but if it is not in the same direction as the displacement, there is no transfer of energy resulting in work being done.

For example, if you push a box horizontally along a surface, and the force you exert is perpendicular to the displacement of the box, no work is done on the box. The force you apply may change the box's direction, but it does not result in a transfer of energy over the displacement. Work is only done when the force and displacement have a component in the same direction.

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