$A$ streamline flow of a liquid of density $\rho$ is passing through a horizontal pipe of cross-sectional area $A_1$ and $A_2$ at two ends. If the pressure of the liquid is $P$ at a point where the flow speed is $v$,then the pressure at another point where the flow speed becomes $3v$ is:

Explain blood flow and heart attack with the help of Bernoulli's principle.

$A$ closed pipe containing liquid showed a pressure $P_1$ by gauge. When the valve was opened, the pressure was reduced to $P_2$. The speed of water flowing out of the pipe is ($\rho$ = density of water).

$A$ sniper fires a rifle bullet into a gasoline tank,making a hole $53.0 \ m$ below the surface of the gasoline. The tank was sealed at $3.10 \ atm$. The stored gasoline has a density of $660 \ kg \ m^{-3}$. The velocity with which gasoline begins to shoot out of the hole is ........ $m \ s^{-1}$.

$A$ manometer connected to a closed tap reads $3.5 \times 10^5 \ N/m^2$. When the valve is opened,the reading of the manometer falls to $3.0 \times 10^5 \ N/m^2$. The velocity of the flow of water is ........ $m/s$.

$A$ horizontal pipe carries water in a streamlined flow. At a point along the pipe,where the cross-sectional area is $10 \text{ cm}^2$,the velocity of water is $1 \text{ ms}^{-1}$ and the pressure is $2000 \text{ Pa}$. What is the pressure of water at another point where the cross-sectional area is $5 \text{ cm}^2$ (in $Pa$)? [Density of water $= 1000 \text{ kgm}^{-3}$]