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Broad-crested weir: formula for maximum discharge For a broad-crested weir of length L with head H over the crest and coefficient of discharge C<sub>d</sub>, select the correct expression for maximum discharge.

Q: Broad-crested weir: formula for maximum discharge For a broad-crested weir of length L with head H over the crest and coefficient of discharge C d , select the correct expression for maximum discharge.

Concept/Approach For free overflow over a broad-crested weir at maximum discharge condition, the theoretical constant is about 1.705; thus Q = 1.71 Cd L H3/2 (SI units when H in metres, Q in m3/s). Final Answer 1.71 Cd × L × H3/2

Difficulty: Easy

0.384 C_d × L × H^1/2
0.384 C_d × L × H^3/2
1.71 C_d × L × H^1/2
1.71 C_d × L × H^3/2

Correct Answer: 1.71 C_d × L × H^3/2

Explanation:

Concept/Approach

For free overflow over a broad-crested weir at maximum discharge condition, the theoretical constant is about 1.705; thus Q = 1.71 C_d L H^3/2 (SI units when H in metres, Q in m³/s).

Final Answer
1.71 C_d × L × H^3/2

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