Two thin circular discs $A$ and $B$ of radii $2 \mathrm{cm}$ and $4 \mathrm{cm}$ are in a liquid at the same depth. $T_A$ is the thrust on $A$ and $T_B$ thrust on $B$. Then $T_A:T_B=$

Water flows through a frictionless duct with a cross-section varying as shown in the figure. Pressure $P$ at points along the axis is represented by

A cylindrical tank has a hole of $1\mathrm{ }{\mathrm{cm}}^2$ in its bottom. If the water is allowed to flow into the tank from a tube above it at the rate of $70\mathrm{ }{\mathrm{cm}}^3 {\mathrm{s}}^{-1}$ then the maximum height up to which water can rise in the tank is :

The velocity of the liquid coming out of a small hole of a large vessel containing two different liquids of densities $2\rho$ and $\rho$as shown in the figure is