Physics
A pulley system with V.R. = 4 is used to lift a load of 175 kgf through a vertical height of 15 m. The effort required is 50 kgf in the downward direction. (g = 10 N kg-1)
Calculate:
(i) Distance moved by the effort.
(ii) Work done by the effort.
(iii) M.A. of the pulley system.
(iv) Efficiency of the pulley system.
Machines
ICSE 2017
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Answer
Given,
V.R. = 4
L = 175 kgf
dL = 15 m
E = 50 kgf
(i) V.R. =
Substituting the values we get,
(ii) Work done by the effort = E x dE
= 50 x 10 x 60
= 3 x 104
(iii) M.A. =
Substituting the values we get,
(iv) Efficiency η =
Substituting the values we get,
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