A machine whose efficiency is 60% has a velocity ratio of 5. If a force of 500N is applied to lift a load P; what is the magnitude of P?

A. 1500N
B. 500N
C. 4166N
D. 750N

Correct Answer:

Option A – 1500N

Explanation

efficiency = (M.A / V.R) x 100/1 => 60/100 = M.A/5
∴M.A = (60 X 5) / 100 = 3
But M.A = Load/Effort; => 3 = Load/500
∴Load = 500 x 3
= 1500N