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Chapter 9: Q. 14 (page 227)

The motor of a crane uses power P to lift a steel beam. By what factor must the motor’s power increase to lift the beam twice as high in half the time?

Short Answer

Expert verified

Power becomes 4P , that is four times.

Step by step solution

01

Given Information

The motor of a crane uses power P to lift a steel beam.

Crane lift the beam twice as high in half the time .

02

Explanation

We know power is defined as P=Wt

Where, W= work done and t=time taken

Now find the power with double the height in half the time

Pnew=2PPnew=2Wt/2Pnew=4WtPnew=4P


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