JEE Mains 05-Sep-2020 Shift 2 Solved Paper

In an experiment to verify Stokes law, a small spherical ball of radius r and density rho falls under gravity through a distance h in air before entering a tank of water. If the terminal velocity of the ball inside water is same as its velocity just before entering the water surface, then the value of h is proportional to :
(ignore viscosity of air)