A 20kg mass is to be pulled up a slope inclined at 30°...
A 20kg mass is to be pulled up a slope inclined at 30° to the horizontal. If efficiency of the plane is 75%. The force required to pull the load up the plane is J [g=10ms−2]
87N
73.5N
133.3N
533.2N
Correct answer is C
V. R = \frac{1}{Sinθ}
m = 20kg
V.R = \frac{1}{Sin 30}
= 2
Efficiency = 75%
Load = mg
= 20 x 10 = 200N
Efficiency = \frac{M.A}{V.R} \times 100
75/100 = \frac{M.A}{2}
M .A = \frac{75 \times 2}{100}
M. A = 1.5
Since M. A. = \frac{\text{Load}}{\text{Force}}
Force = \frac{200}{1.5}
= 133.3N