Question

The diameter of a water drop is 0.003 mm. It is falling in air. Find out the terminal velocity of air. The coefficient of viscosity is 1.8 x 10^-5 kg m^-1s^-1. The density of air is negligible.

Answer 1

r = \(\frac{0.003}{2}\ mm = \frac{3\times10^{-6}}{2}\) m = 1.5 x 10^-6 m; σ = 0; ρ = 10³ kg/m³

η = 1.8 x 10^-5 kg/ms; v_t = ?