Question

In the figure shown water is filled in a symmetrical container. Four pistons of equal area $A$ are used at the four opening to keep the water in equilibrium. Now an additional force $F$ is applied at each piston. The increase in the pressure at the centre of the container due to this addition is

• A. $\frac{F}{A}$
• B. $\frac{2F}{A}$
• C. $\frac{4F}{A}$
• D. $0$

Answer 1

The correct option is A $\frac{F}{A}$

Net force applied $=4F$

Net area acted upon $=4A$

Charge in pressure $=\frac{4F}{4A}=\frac{F}{A}$

This can easily be understood as follows

$F_1=F$ is applied & $\frac{F}{A}$ is transferred to all other

three pistons by pascal's law. And $F_2,F_3,F_4$

come into balancing the transferred pressure and

thus keeping the water in equilibrium. So, they

do not transfer additional pressure at the centre.

So change in pressure $\Delta P=\frac{F}{A}$