Question

A non-viscous liquid is flowing through a non-uniform pipe from section $A$ to section $B$ as shown in the figure. Cross sectional area of the pipe at $A$ is less then that at $B$. Which of the following statement are correct?

• A. The pressure at $A$ is greater than that at $B$
• B. Velocity at $A$ is greater than at $B$
• C. Total energy per unit volume of the liquid is greater at $A$ then at $B$
• D. Axis of the pipe cannot be horizontal

Answer 1

The correct option is B Velocity at $A$ is greater than at $B$

Let area of pipe

at $A=A_1$

at $B=B_1$ [Ref. image 1]

Applying equation of continuity at $A\&B$

$A_1{V}_1=A_2{V}_2$ ($A_1\&V_2$ are velocity of liquid at A & B)

as $A_1<A_2$

$\Rightarrow V_1>V_2$ option B