The weight of an aeroplane flying in the air is balanced by:

Water containing air bubbles flows without turbulence through a horizontal pipe which has a region of narrow cross-section. In this region,the bubbles

$A$ horizontal pipeline carries water in a stream-line flow. At a point along the pipe, where the cross-sectional area is $10 \,cm^2$, the velocity of water is $1 \,m/s$ and the pressure is $2000 \,Pa$. The pressure of water at another point where the cross-sectional area is $5 \,cm^2$ is (Given: density of water $\rho = 1000 \,kg/m^3$) (in $\,Pa$)

$A$ train with cross-sectional area $S_t$ is moving with speed $v_t$ inside a long tunnel of cross-sectional area $S_0$ $(S_0 = 4S_t)$. Assume that almost all the air (density $\rho$) in front of the train flows back between its sides and the walls of the tunnel. Also,the air flow with respect to the train is steady and laminar. Take the ambient pressure and that inside the train to be $p_0$. If the pressure in the region between the sides of the train and the tunnel walls is $p$,then $p_0 - p = \frac{7}{2N} \rho v_t^2$. The value of $N$ is. . . . .

An $L$-shaped glass tube is just immersed in flowing water as shown. If the speed of the water current is $V$,then the height $h$ up to which the water rises will be

Water is flowing through a horizontal pipe of non-uniform cross-section. At the extreme narrow portion of the pipe, the water will have