Question

A steel ball with radius 0.3 mm is falling with velocity of 2 m/s through a tube filled with glycerine. Calculate viscous force acting on the steel ball.

[Given: `N_"glycerine"` = 0.833 Ns/m²]

Answer 1

Given: r = 0.3 m.m = 0.3 × 10⁻³ m

v = 2 m/s

η = 0.833 Ns/m²

We have:

F = 6 π η r v

= 6 × 3.142 × 0.833 × 0.3 × 10⁻³ × 2

= 9.422 × 10⁻³ N