Question

The processes of removal of particles in a rapid sand filter with their description is given in the table.

Process	Description
(i) Straining	P: Removes only particles in the water large enough to get caught in the pores of the filter
(ii) Sedimentation	Q: Larger and heavier particles do not follow the fluid streamline around the sand grain and settle on the grain
(iii) Interception	R: Particles that do follow the streamline, but are too large and are caught because they brush up against the sand grains
(iv) Diffusion	S: Very small particles are experiencing Brownian motion and may collide with the sand grains by chance

Select the correct match.

• A. i- S; ii-P; iii-Q; iv-R
• B. i-Q; ii-R; iii-S; iv-P
• C. i-R; ii- S; iii- P; iv-Q
• D. i-P; ii-Q; iii-R; iv-S

Answer 1

Answer: (D)

i-P; ii-Q; iii-R; iv-S

Answer 2

The correct answer is (C) : Mycobacterium bovis