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Question
A fixed pulley is driven by a 100 kg mass falling at a rate of 8.0 m in 4.0 s. It lifts a load of 75.0 kgf. Calculate : the height to which the load is raised in 4.0 s.
Solution
Ratio of `(M.A.)/(V.R) = "Efficiency"`
`("Load"/"Effort")/("distance moved by effort"/"distance moved by load") = 3/4`
`(75/100)/(8/d_L) =3/4`
`75/100 xx d_L/8 = 3/4`
`3/32 d_L = 3/4`
`d_L = 3/4 xx 32/3 = 8 m`
The height to which the load is raised is 8 m.
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