The terminal velocity v t of the spherical rain drop depends on the radius r of the spherical rain drop as

Step-by-step solution

The terminal velocity of a sphere of radius r and density ρ , immersed in a liquid of density σ and viscosity η is given by v T = 2 9 ρ - σ r 2 g η Hence, for spherical raindrop, v T ∝ r 2 .