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A lift of mass 400 kg is hung by a wire....

A lift of mass 400 kg is hung by a wire. Calculate the tension in the wire when the lift is (i) at rest (ii) moving upwards with a constant velocity of `1ms^(-1)` (iii) moving upwards with an acceleration of `2ms^(-2)` and (iv) moving downwards with an acceleration of `2ms^(-2)`.

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The correct Answer is:
(i) 3920 N (ii) 3920 N (iii) 4720 N (iv) 3120 N
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