Question

Calculate the critical velocity (m/sec) of a channel using Kennedy's theory, the depth of flow is 3 m.

• A. 0.84
• B. 1.11
• C. 2.7
• D. 6

Answer 1

The correct option is B 1.11

$\text{Given that:}$
Depth of flow (y) = 3m

Critical velocity by Kennedy's theory is
$V_0=0.55m{y}^{0.64}$

$V_0=\text{Critical velocity in the channel (m/s)}$
y = Water depth in channel (in meters);
m = Critical velocity ratio

Then,
$V_0=0.55\times 1\times \left(3{)}^{0.64}\right[\because m=1]$
$V_0=1.11m/s$

Hence, the critical velocity of a channel is 1.11 m/s