Civil Engineering - Irrigation

V and R are the regime mean velocity and hydraulic mean depth respectively in metres. Lacey's silt factor f is

Pick up the correct statement from the following

According to Kennedy, the critical velocity (V₀) in metres in a channel is the mean velocity which keeps the channel free from silting or scouring. Its value is given by (where m is critical velocity ratio and D is the depth of the channel).

According to Lacey, depth of scour in a river depends upon the straightness of the reach. If D is the depth of scour in regime flow in a right angled bend, it is

The width of a dowla is generally kept between 30 to 60 cm and its height above the road level should invariably be more than