Question

Find the discharge of water flowing over a rectangular notch of 1.5 m length when the constant head over the notch is 275 mm. Take Cd = .60

(a) 400 lit/s

(b) 465 lit/s

(c) 385 lit/s

(d) 575 lit/s

The question was posed to me in an interview for job.

Question is from Discharge over a Rectangular, Triangular, Trapezoidal & Stepped Notch in section Orifices, Mouthpieces, Notches and Weirs of Fluid Mechanics

Answer 1

The correct option is (c) 385 lit/s

For explanation I would say: Q = 2/3 * L * √2g * H^1.5

                       = .67 * 1.5 * √19.62 * .275^1.5

                       = .385 m^3/min.