Question

A liquid is following in a horizontal pipe of non-uniform cross section. Which of the following quantities remain change with respect to time ?

• A. Kinetic energy per unit volume
• B. Pressure energy per unit volume
• C. Potential energy per unit volume
• D. Speed of flow

Answer 1

The correct option is C Potential energy per unit volume

$\frac{1}{2}\rho v_1^2+P_1+\rho gh=$ Constant $\to$ Bernalli's eq
$K.E.$ per unit volume of fluid
Pressure energy per unit volume
Gravitational $P.E.$ per unit volume (w.r.t of ref)
speed of flow will change
$K.E.$ depends on speed $\to K.E.$ will change
$\frac{1}{2}\rho v_1^2+P=$ constant

This will also change