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liq [111]
3 years ago
7

A crane used 250,000 Joules of work to move a beam to the top of a building in 20 seconds. How much power did the crane use?

Physics
1 answer:
maria [59]3 years ago
7 0

Answer:

12500W

Explanation:

Given parameters:

Work done  = 250000J

Time taken  = 20s

Unknown:

Power of the crane = ?

Solution:

Power is the defined as the rate at which work is being done;

  Mathematically;

        Power = \frac{work done}{time }

 insert the parameters and solve;

      Power  = \frac{250000}{20}   = 12500W

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3 years ago
A 125 g pendulum bob hung on a string of length 35 cm has the same period as when the bob is hung from a spring and caused to os
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Answer:

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Explanation:

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k = (9.81\ m/s^2)(\frac{0.125\ kg}{0.35\ m})\\\\

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4 0
3 years ago
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