The efficiency of a wheel and axle is 100% and the ratio of their radii is 5:1. calculate the effort required to lift a load of mass 20kg using this machine, [g = 10 m s\(^{-2}\)]
- 20N
- 25N
-
40N
- 100N
The correct answer is: C
Explanation
VR = 5:1 or 5
Load = 20kg or 200N
MA = \(\frac{200}{E}\)
Efficiency% = \(\frac{MA}{VR} * 100\)
100% = \(\frac{200}{5E} * 100\)
5E = 200
E = 40