Question

Water flows through a horizontal pipe of radius 'r' at a speed V. If the radius of the pipe is doubled,the speed of flow of water under similar conditions is:

• A. $2V$
• B. $\frac{V}{2}$
• C. $\frac{V}{4}$
• D. $4V$

Answer 1

Answer: (C)

$\frac{V}{4}$

From $e{q}^n$ of continity
$V\pi r^2=V_B\pi (2r{)}^2$
$V_B=\frac{V}{4}$