Water flows steadily through a horizontal pipe of variable cross-section. If the pressure of water is $P$ at a point where flow speed is $v$ , the pressure at another point where the flow speed is $2v$ , is (Take density of water as $\rho $ )

Water is flowing continuously from a tap having an internal diameter $8 \times 10^{-3}\ m $ The water velocity as it leaves the tap is $0.4$ $ms^{-1}$ છે. The diameter of the water stream at a distance $2  \times 10^{-1}$ $m$ below the tap is close to .......$\times 10^{-3}\;m$

Water is flowing through a horizontal tube having cross-sectional areas of its two ends being $A$ and $A'$ such that the ratio $A/A'$ is $5$ છે.જો  If the pressure difference of water between the two ends is $3 \times 10^5\, N\, m^{-2}$, the velocity of water with which it enters the tube will be ......... $m s^{-1}$ (neglect gravity effects)

$Assertion :$ The velocity of flow of a liquid is smaller when pressure is larger and vice-versa.
$Reason :$ According to Bernoulli’s theorem, for the stream line flow of an ideal liquid, the total energy per unit mass remains constant.

Fig. represents vertical sections of four wings moving horizontally in air. In which case the force is upwards

Water is flowing through a channel (lying in a vertical plane) as shown in the figure. Three sections $A, B$ and $C$ are shown. Sections $B$ and $C$ have equal area of cross section. If $P_A, P_B$ and $P_C$ are the pressures at $A, B$ and $C$ respectively then