What effort will a machine of efficiency 90% apply to lift a load of 180N if its efforts arm is twice as long as its load arm?

A. 80N
B. 90N
C. 100N
D. 120N

Correct Answer:

Option C – 100N

Explanation

M.A. = Eff×V.R/100

M.A. = 90×2/100

M.A. = 1.8

E = L/M.A.

E = 180/1.8

E = 100N