A plane inclined at an angle at 30° to the horizontal has an efficiency of 50%. The force parallel to the plane required to push a load of 120 N uniformly up the plane is?

A. 40√3N
B. 60N
C. 120N
D. 200N
E. 240N

Correct Answer:

Option C – 120N

Explanation

E = M.A/V.R ; 50/100 = M.A/2
M.A = 1; L/E = 1
E = L = 120N