A ball of mass m and radius r is released in viscous liquid, The value of its terminal velocity is proportional to
1 /r only
m/r
(m/r)1/2
m only
we know that vT=29×r2(ρ−σ)η×g =29×r3ρ(1−σ/ρ)grη or vT∝mr ∵m∝r3ρ