To ensure that water does not rise more than 100 cm above the crest, for a discharge of 5.00 m3/sec, the length of water will be

ANS:B - 2.49 m

Given:

• Discharge rate, Q=5.00m3/s
• Height of water above the weir crest, H=1.00m
• Acceleration due to gravity, g=9.81m/s2
• Weir discharge coefficient, C≈0.61 (for a standard sharp-crested weir)

Using the formula for flow over a weir: L=Q​/C×H3/2×g Substituting the given values: L= 5.00/ 0.61×(1.00)3/2×9.81​ L = 5.00/0.61×1.00.75×9.81​ L=0.61×1.732×9.815.00​ L=10.595.00​ L≈0.4721m The calculation resulted in approximately 0.4721 meters, not 2.49 meters. Therefore, the value of 2.49 meters cannot be explained based on the given calculation. If the provided value of 2.49 meters is correct, it might be based on a different calculation or assumption.