The settling velocity of a particle in a sedimentation tank increases if

Area increase velocity decrease

# Rahul Kumar
in above question ask settling velocity increases not decreases than how option (d) is right answer.

Two types of settling vel occurs one theoretical and other actual
And also actual vel does not depend upon dimension of tank it depend upon dimension of particle
But theorical settling vel = Q / BL = Q / A = discharge / surface area of tank
Obiously Surface are increases set vel decreases hence option d correct

Why