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
Verified Correct Answer: A.
Physical Principles & Numerical Solution
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
Source: WAEC / JAMB / NECO Classroom Archive (Record #12891)