Question

A piezometer tube is used to measure pressure of a liquid flowing inside a pipe as shown below. If the liquid is having a specific weight of 9810 N/m${}^2$ then assuming undisturbed flow in pipe diameter from point A in both upstream and downstream and also assuming that the atmospheric pressure is negligible at point A, which of the following is true:

• A. Pressure at point A is 245 Pa and is static
• B. Pressure at point A is 245 Pa and is dynamic
• C. Pressure at point A is 245 Pa and is stagnation
• D. None of the above

Answer 1

The correct option is A Pressure at point A is 245 Pa and is static

$P=\rho .g.h$

$Given\rho .g=9810N/m^2$

$\therefore P=9810\times 25\times {10}^{-3}$

$=245.25Pa$

Since flow is having undisturbed pressure, so it is static.