Question

A 3-m wide rectangular channel has a flow velocity of 1.8 m/s when the depth of flow is 1.2 m. what will be the flow velocity when the depth of flow is increased to 3 m?

Answer 1

The flow velocity reduces to 0.72 m/s

Step-by-step explanation:

According to the equation of continuity discharge in the channel should remain same

Thus we have

`A_(1)V_(1)=A_(2)V_(2)`

For a rectangular channel we have
`Area=Depth* Width`

Applying values in the continuity equation and since the width of the channel remains constant 3.0 m we have

`3* 1.8* 1.2=3* 3* V_(2)\\\\\therefore V_(2)=(6.48)/(9)=0.72m/s`