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The head of water over a rectangular weir is 28 cm. The length of the crest of the weir end contraction suppressed is 1.27 m. Find the discharge using the Francis formula.

The head of water over a rectangular weir is 28 cm. The length of the crest of the weir end contraction suppressed is 1.27 m. Find the discharge using the Francis formula. Correct Answer 0.346 m3/s

Q = m * L * (2*g)0.5 * H1.5 m = ⅔ * Cd = 0.405 + 0.003/H = 0.405 + 0.003/0.28 Q = 0.346 m3/s.

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