$A$ hydraulic automobile lift is designed to lift cars with a maximum mass of $3000 \, kg$. The area of cross-section of the piston carrying the load is $425 \, cm^{2}$. What is the maximum pressure the smaller piston would have to bear?

Give two uses of Pascal's law.

$A$ hydraulic press containing water has two arms with diameters as shown in the figure. $A$ force of $10 \,N$ is applied on the surface of water in the thinner arm. The force required to be applied on the surface of water in the thicker arm to maintain equilibrium of water is . . . . . . $N$.

$A$ hydraulic press can lift $100\, kg$ when a mass $'m'$ is placed on the smaller piston. It can lift ......... $kg$ when the diameter of the larger piston is increased by $4$ times and that of the smaller piston is decreased by $4$ times,keeping the same mass $'m'$ on the smaller piston.

The area of cross-section of the wider tube shown in the figure is $800\,cm^2$. If a mass of $12\,kg$ is placed on the massless piston,the difference in the heights $h$ in the level of water in the two tubes is ........ $m$.

$A$ tall tank filled with water has an irregular shape as shown. The wall $CD$ makes an angle of $45^{\circ}$ with the horizontal,the wall $AB$ is normal to the base $BC$. The lengths $AB$ and $CD$ are much smaller than the height $h$ of water (figure not to scale). Let $p_1, p_2$ and $p_3$ be the pressures exerted by the water on the wall $AB$,base $BC$ and the wall $CD$ respectively. Density of water is $\rho$ and $g$ is acceleration due to gravity. Then,approximately