Question

The graph shows load against effort for a lever with load and effort on the same side of the fulcrum.

1. Which feature of the load and effort graph must be calculated to determine mechanical advantage?
2. Which class does this lever belong to?

Answer 1

(a) The gradient (slope) of the load–effort graph must be calculated to determine the mechanical advantage.

Mechanical Advantage \[=\frac{\text{Load}}{\text{Effort}}\]

From the graph:

M.A. = \[\frac{20}{10}\] = 2

So, mechanical advantage is 2.

(b) Since the load and effort act on the same side of the fulcrum, and the mechanical advantage is greater than 1, the lever is a second-class lever. In a second-class lever, the load lies between the fulcrum and the effort, which allows a smaller effort to overcome a larger load.