Discharge Over Trapezoidal and Stepped Notch or Weir

Q. The discharge over a broad crested weir is maximum when the depth of flow is

1. $\frac{H}{3}$
2. $\frac{2H}{3}$
3. $\frac{H}{2}$
4. $\frac{2H}{5}$

Q. A submerged weir is one in which the water level on the down stream side of the weir is:

1. Just at the crest level
2. Below the crest level
3. Above crest level
4. At same elevation as water surface on upstream

Q. A Cipolletti weir discharges water with the head of water over the crest being 250 mm. If the head due to velocity of approach is 0.01 m, What will be the excess percentage of flow, when corrected for velocity of approach as compared to when not so corrected?

1. 3.2%
2. 4.2%
3. 5.3%
4. 6.3%

Q.

Among weirs used in open flow metrology, critical depth of the flow is the relevant criterion in:

1. Broad-crested weir

2. Cippoletti weir

3. Parabolic weir

4. Sharp-crested weir

Q. An error of 0.5% in the measurement of head in a V-notch causes an error of

1. 0.5% in the discharge
2. 1.0% in the discharge
3. 1.25% in the discharge
4. 1.5% in the discharge

Q.

For accurate flow measurement in open channels, an arrangement for aeration under the nappe is necessary when the weir used is

1. Contracted rectangular

2. Suppressed rectangular

3. Submerged contracted rectangular

4. Triangular

Q. If the error in the measurement of head in a 'V' notch is 1%, then the error in the measurement of discharge will be

1. 1%
2. 1.5%
3. 2%
4. 2.5%

Q.

A depth-discharge relationship of the canal section is maintained at a notch fall because the sill of the notches is

1. Level with downstream canal bed

2. Below the upstream canal bed

3. Level with upstream canal bed

4. Above the upstream canal bed

Q. Consider the following measuring structures:
1. Submerged broad-crested weir
2. Free broad-crested weir
3. Free sharp-crested weir
4. Free ogee spillway
The correct sequence of the increasing order of the discharge coefficient of these structures is

1. 1, 2, 4, 3
2. 2, 1, 3, 4
3. 2, 1, 4, 3
4. 1, 2, 3, 4