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Q. A heavy iron bar of weight W has one end resting on the ground and the other on the shoulder of a person. The bar makes an angle θ with the horizontal. The weight experienced by the person is:

Correct Answer: W/2

Taking moments about the end touching the ground,

F × L cosθ = W × (L/2) cosθ

⇒ F = W/2

Hence the force experienced by the person is W/2, independent of θ.

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