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3 years ago

A car is being lifted by a crane so that it moves upwards at a constant speed.

Physics

1 answer:

anygoal [31]3 years ago

7 0

Answer:

Explanation:

Work done is defined as the product of force and the displacement in the direction of force.

W = F x d x Cos θ

Where, θ be the angle between force and the displacement.

The force of gravity acts downwards and the displacement is in upward, so the angle is 180. cos 180 = -1 , so the work done by the force of gravity is negative.

The force of rope acting in upwards direction and displacement also in upwards direction.

So, the work done is positive

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nikitadnepr [17]

Answer:

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Explanation:

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It is given that,

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Answer:

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