Question

Find the discharge over a cipolletti weir of length 1.5 m when the head over the weir is 0.85 m. Take Cd = 0.61.

(a) 2.12 m^3/s

(b) 1.25 m^3/s

(c) 2.5 m^3/s

(d) 1.5 m^3/s

I got this question during a job interview.

This intriguing question comes from Time Required to Empty a Reservoir with  Weirs or Notches in chapter Orifices, Mouthpieces, Notches and Weirs of Fluid Mechanics

Answer 1

Correct choice is (a) 2.12 m^3/s

The explanation is: Q = ⅔ * Cd * L * (2g)^0.5 * H^1.5

                        = 2.12 m^3/s.