Question

A machine lifts a load of 2 tonnes weight with an effort of 100 kg weight. When the effort moves through 5 m the load moves through 0.2 m. The efficiency of the machine is

• A. 20%
• B. 40%
• C. 80%
• D. 0.8%

Answer 1

Answer: (C)

80%

Efficiency $=\frac{Powe{r}_{load}}{{Power}_{effort}}\times 100$

$=\frac{2\times {10}^3\times 0.2}{5\times {10}^2}\times 100$

$=\frac{4}{5}\times 100=80$%