Question

In the diagram below the area of the small piston is 2m2 and the large piston is 120 m2. If the small piston is pushed down with a force of 20N, calculate the pressure exerted on the liquid. If the same pressure is transmitted by the liquid to act on the large piston, calculate the force acting on the large piston. Compare the force acting on the large piston with that being exerted on the smaller piston.

Answer 1

Given that,

Area of the small piston is 2 m² and that of large piston is 120 m². The small piston is pushed down with a force of 20 N.

To find,

The force acting on the large piston.

Solution,

As the pressure is transmitted by the liquid to act on the large piston, it  would mean that,

$\dfrac{F_1}{A_1}=\dfrac{F_2}{A_2}$

A₁ = 2 m², A₂ = 120 m², F₁ = 20 N, F₂ = ?

So,

$F_2=\dfrac{F_1A_2}{A_1}\\\\F_2=\dfrac{20\times 120}{2}\\\\F_2=1200\ N$

So, 1200 N of force is acting on the large piston.