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 motor has an electrical input of 30 kJ and is used to raise 100 kg l

1.	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))
Answer» 0.0075 `83.5%` 0.75 `17.5%` SOLUTION :`ETA=("output")/("input")XX100=(100xx10xx25)/(30xx1000)xx100` =`(250)/(3)=83.3%`

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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))

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