Question

Calculate the efficiency(%) of a machine that overcomes the resistance of 800N through a distance of 0.12m, while an effort of 160N acts through a distance of 0.72m.

Answer 1

1. Definition:

Efficiency(%):

It is the ratio of mechanical advantage(M.A) to the velocity ratio(V.R).

Efficiency(%) = $\frac{M.A}{V.R}$

Velocity ratio:(V.R)

It is the ratio of distance traveled by the effort to the distance traveled by the load.

Velocity ratio = $\frac{effortarm}{loadarm}$

Mechanical advantage:(M.A)

It is the ratio of load to effort.

Mechanical advantage = $\frac{load}{effort}$

2. Solution:

Given that,

load = 800N

load arm = 0.12m

Effort = 160N

effort arm = 0.72m

Velocity ratio =$\frac{effortarm}{loadarm}$= $\frac{0.72}{0.12}$=6

Mechanical advantage = $\frac{load}{effort}$= $\frac{800}{160}$=5

Efficiency = $\frac{M.A}{V.R}$= $\frac{5}{6}$x 100 = 83.33%

3. Conclusion:

Hence, the efficiency is 83.33%.