**581. The falling drop of rainwater become spherical due to _________________?**

**A. Surface Tension**

B. Compressibility

C. Capillary

D. None of these

**582. Piezometer tube is open to both ends mostly used to measure ____________________?**

A. Atmospheric pressure**B. gauge pressure**

C. Vacuum pressure

D. absolute pressure

**583. A flow in which velocity of water particles is same at all sections is called ____________________?**

A. Steady flow**B. Uniform flow**

C. Compressible flow

D. Laminar flow

**584. Flow in which each liquid particle has a definite path is called _____________________?**

A. Steady flow

B. uniform flow**C. Laminar flow**

D. Transitional flow

**585. For a perfect incompressible liquid flowing in a continuous stream, the total energy of a particle remain the same, while the liquid particle move from one point to another this statement is called ___________________?**

A. Continuity Equation

B. Pascal s law**C. Bernoulli equation**

D. Archimede’s principle

**586. The discharge over a rectangular notch is determined by _____________________?**

A. 2/3 cd. b (2 gh) 1/2

B. 2/3 cd. B (2g) 1/2 H**C. 2/3 cd. B (2g) 1/2 H3/2**

D. 2/3 cd. b (2g) 1/2 H 5/2

**587. The total energy line lies over the hydraulic gradient line by an amount equal to________________?**

**A. v2/2g**

B. v2/g

C. v/2g

D. v/g

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

A. Gives max. Discharge

B. Has minimum wetted perimeter

C. Involves lesser excavation**D. All of these**

**589. 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

**590. if the depth of water in an open channel is greater than the critical depth, the flow is called________________?**

A. Critical depth

B. Non-critical flow**C. Sub-critical flow**

D. Shooting flow