134. The Empirical formula Q = 0.405 for discharge over large rectangular weirs, is known as

A. Francis formula

B. Bazin formula

C. Rehbook formula

D. Kutter's formula.

135. When water flows over a rectangular suppressed weir, the negative pressure created beneath the nappe

A. increases the discharge

B. decreases the discharge

C. does not effect the discharge

D. none of these.

136. When no air is left below the nappe and water stream adheres to the down stream face of the weir, it is known as

A. free nappe

B. depressed nappe

C. clinging nappe

D. none of these.

137. With a clinging nappe of a weir, the excess discharge, is

A. 6% to 7%

B. 8% to 10%

C.) 18% to 20%

D. 25% to 30%

138. The notch angle for maximum discharge over a triangular notch, is

A. 30?

B. 60?

C. 90?

D. 120?.

139. A triangular notch is preferred to a rectangular notch because

A. only one reading is required

B. its formula is simple to remember

C. it gives more accurate results for low discharge

D. all the above.

140. Manning's formula is used for

A. flow in open channels

B. head loss due to friction in open channels

C. head loss due to friction in pipes flowing full

D. flow in pipes.

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