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A motor has an electrical input of 30 kJ...

A motor has an electrical input of 30 kJ and is used to raise 100 kg load to a height of 25 m when fitted to a crane winch. What is the efficienty of winch ?
`(g=10 ms^(-1))`

A

0.0075

B

`83.5%`

C

0.75

D

`17.5%`

Text Solution

Verified by Experts

The correct Answer is:
b
`eta=("output")/("input")xx100=(100xx10xx25)/(30xx1000)xx100`
=`(250)/(3)=83.3%`
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