The diagram (figure) shows a venturimeter, through which water is flowing. The speed of water at $X$ is $2\,cm/s$. The speed of water at $Y$ (taking $g = 1000\,cm/s^2$ ) is ........ $cm/s$

A homogeneous solid cylinder of length $L (L < H/2)$ , cross-sectional area $A$ is immersed such that it floats with its axis vertical at the liquid-liquid interface with length $L/4$ in the denser liquid as shown in the figure. The lower density liquid is open to atmosphere having pressure $P_0$ . Then, density $D$ of solid is given by

A boat carrying a number of stones is floating in a water tank. If the stones are unloaded into water, the water level in the tank will ............

Water falls from a tap, down the streamline

A cylindrical vessel filled with water upto the height $H$ becomes empty in time $t_0$ due to a small hole at the bottom of the vessel. If water is filled to a height $4H$ it will flow out in time

A cubical block is floating in a liquid with half of its volume immersed in the liquid. When the whole system accelerates upwards with a net acceleration of $g/3$ The fraction of volume immersed in the liquid will be