• The question is one of the civil engineering subjects centered on gates in fluid mechanics
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1.A 4-m-long quarter-circular gate of radius 3 m and of negligible weight is hinged about its upper edge A, as shown in above. The gate controls the flow of water over the ledge at B, where the gate is presses by a spring. Determine the minimum spring force required to keep the gate closed when the water level rises to A at the upper edge of the gate. 3 m B Spring