A channel is said lo be of most economical cross section, for a given cross-sectional area and bed slope when it __________________?

Related Mcqs:

1. When a weir is constructed, the downstream .bed of the river goes on eroding and consequently causes progressive lowering of the bed on downstream of weir called__________________?

   A. Retrogression
   B. Lowering down of bed
   C. Ponding on down stream
   D. All are correct

2. That part of the flow in a stream comes from sub-soil or valley, may be beneath the top surface of channel bed is called__________________?

   A. Sub-surface flow
   B. Base flow
   C. Ground flow
   D. All are correct

3. An open cut in the canal bank. with bed and sides to escape canal water through a lead channel to mix water in a nearby drain is called _____________________?

   A. Inlet
   B. Out let
   C. Module
   D. Exit

4. in most economical Trapezoidal section, half of the Top width is equal to _________________?

   A. Bottom width of channel
   B. Depth of channel
   C. Sloping side of channel
   D. None of these

5. The most economical central angle of an arch dam is made at ___________________?

   A. 123º
   B. 133!
   C. 143º
   D. 153º

6. For an economical design of gravity dam, the shear friction factor causec compression strength should lie between____________________?

   A. 1.5 to 4.0
   B. 2.0 to 4.0
   C. 2.5 to 4.5
   D. 3 to 5

7. When the rate of change of discharge of outlet equals the rate of change of discharge of the channel, the out let is called __________________?

   A. Sensitive
   B. Flexible
   C. Proportional
   D. Non-flexible

8. When the weight of weir balances the up lift pressure caused by the head of the water seeping below the weir bed is called ___________________?

   A. Cippollite weir
   B. Broad crested weir
   C. Gravity weir
   D. Non-gravity weir

9. When the high flood level of the drain is sufficiently below the bed of the Canal that the drainage water flows freely under gravity, such structure is called___________________?

   A. Aqueduct
   B. Syphon-aqueduct
   C. Cross-Drainage
   D. Non-gravity structure

10. If a river or stream is collecting sediment and is building up dunes in its bed is called ______________________?

    A. Stable river
    B. Sub-stable river
    C. Aggrading river
    D. Sediment river