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प्रश्न
A fixed pulley is driven by a 100 kg mass falling at a rate of 8.0 m in 4.0s. It lifts a load of 75.0 kgf. Calculate the power input to the pulley taking the force of gravity on 1 kg as 10 N.
उत्तर
Load = 75.0 kgf
Mass of falling object = 100 kg
Displacement of effort = 8.0 m
Time taken = 4.0s
Effort = 100 × 10 = 1000 kgf
Power Input
`"P"_"in" = "displacement × effort"/"time"`
= `(8 ×1000)/4`
= 2000 W
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