The velocity of kerosene in a horizontal pipe is $5 \ m/s$. What is the velocity head in $m$? (Take $g = 10 \ m/s^2$)

Can Bernoulli's equation be used to describe the flow of water through a rapid in a river? Explain.

Water flows in a streamline motion through a horizontal pipe of circular cross-section. The pressure difference of water between $P$ and $Q$ is $15 \text{ Nm}^{-2}$. The area of cross-section at $P$ and $Q$ are $40 \text{ cm}^2$ and $20 \text{ cm}^2$, respectively. The rate of flow of water through the pipe, in $\text{cm}^3\text{s}^{-1}$, is : [Take density of water = $1000 \text{ kg m}^{-3}$]

What is a venturi-meter? Explain its construction and working.

$A$ wind with speed $50 \,m/s$ blows parallel to the roof of a house. The area of the roof is $300 \,m^2$. Assume that the pressure inside the house is atmospheric pressure. The density of air is $1.2 \,kg/m^3$. The magnitude of the force exerted by the wind on the roof will be:

Write the limitations of Bernoulli's equation.