Question

Water is flowing through a horizontal pipe in streamline flow. At the narrowest part of the pipe

• A. velocity is maximum and pressure is minimum
• B. pressure is maximum and velocity is minimum
• C. both the pressure and velocity are maximum
• D. both the velocity and pressure are minimum

Answer 1

The correct option is A velocity is maximum and pressure is minimum

In streamline flow, the product of cross section area and velocity remains constant (equation of continuity). So in the narrowest part of the pipe velocity is maximum.
And from Bernoulli's theorem, we know that the sum of potential energy, kinetic energy and pressure energy remains constant. Since pipe is horizontal potential energy is equal at all the points. So in the narrowest part of pipe pressure (pressure energy) will be minimum because velocity (kinetic energy) is maximum in the narrowest part.