GATE 2020 CE (CE2) – Question 60
A hydraulic jump in a triangular V-channel of side slopes 1:1 vertical to horizontal has sequent depths 0.5 and 1.5 m. Find discharge (m³/s), to two decimals.
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Correct answer: 1.7 to 1.76
Explanation
For a 1:1 triangular channel, $A=y^2$ and hydrostatic specific-force term is $y^3/3$. Equal momentum before and after the jump gives $$\frac{Q^2}{g}\left(\frac1{y_1^2}-\frac1{y_2^2}\right)=\frac{y_2^3-y_1^3}{3}.$$ Substitution gives **Q = 1.73 m³/s**.