(a) The rectangular sharp-crested weir shown in Fig. P10.73a is used to maintain a r...

(a) The rectangular sharp-crested weir shown in Fig. P10.73a is used to maintain a relatively constant depth in the channel upstream of the weir. How much deeper will the water be upstream of the weir during a flood when the flowrate is 45 ft₃/s compared to normal conditions when the flowrate is 30 ft³/s? Assume the weir coefficient remains constant at C_wr = 0.62. (b) Repeat the calculations if the weir of part (a) is replaced by a rectangular sharp-crested “duck bill” weir that is oriented at an angle of 30° relative to the channel centerline as shown in Fig. P10.73b. The weir coefficient remains the same.