In class III lever, the distance from the fulcrum to the load is 100 cm and the distance from the effort to the load is 10 cm. Calculate the МА.

Given,

• Distance between the fulcrum and the load = Load arm = 100 cm
• Distance between the load and the effort = 10 cm

Now,

Effort arm = Distance between the fulcrum and the load - Distance between the load and the effort = 100 - 10 = 90 cm

As, mechanical advantage of a lever is given by the ratio of the effort arm to the load arm i.e.,

$\text {Mechanical Advantage (M.A.)} = \dfrac{\text {Effort arm}}{\text {Load arm}}\\[1em] \Rightarrow \text {M.A.} = \dfrac {90}{100}\\[1em] \Rightarrow \text {M.A.} = 0.9$

So, the MА of class III lever is 0.9.