Question

A resistance of 500 N is overcome by a machine of V.R. 5 and efficiency 80%. Find (a) mechanical advantage (b) effort required to overcome resistance.

Answer 1

\[ \text{(a) } \eta = \frac{\text{MA}}{\text{VR}} \]

\[ \therefore \text{MA} = \eta\,\text{VR}\]

= \[\frac{80}{100} \times 5\]

= 4

\[ \text{(b) MA} = \frac{l}{E} \]

\[ \therefore E = \frac{l}{\text{MA}} \]

= \[\frac{500}{4}\]

= 125 N