A. The bottom is silted
B. The bottom is scoured
C. Both silting and scouring occur at the bottom
D. Neither silting nor scouring occurs at the bottom
A. 1 in 60
B. 1 in 100
C. 1 in 120
D. None of these
A. A sedimentation tank and an activated sludge treatment plant
B. A plant consisting of Imhoff tanks with low rate trickling filters
C. Sedimentation tanks with high rate trickling filters
D. None of these
A. the direction and magnitude of the velocity at all points are identical
B. the velocity of successive fluid par-ticles, at any point, is the same at suc-cessive periods of time
C. the magnitude aricf direction of the velocity do not change from point to point in the fluid
D. the fluid particles move in plane or parallel planes and the streamline pat-terns are identical in each plane
E. velocity, depth, pressure, etc. change from point to point in the fluid flow
A. 200 ppm
B. 225 ppm
C. 250 ppm
D. None of these
A. force of adhesion
B. force of cohesion
C. force of friction
D. force of diffusion
E. none of die above
A. Manually
B. Mechanically
C. Hydraulically
D. Electrically