The efficiency of the pulley system shown above is 80%. find the effort E required to lift the load of 1200N
-
A.
275N -
B.
325N -
C.
375N -
D.
573N
Correct Answer: Option C
Explanation
VR = No. of pulleys = 4
Efficiency = M.A/V.R x 100% = load
Effort x 100%_V.R
∴80 = 1200 x 100 x 1100__Effort4
∴ Effort = 1200 x 100 = 375N_80 x 4