Physics (AS & A Level) · Feb / March 2022 · Paper 22 · Question 1

A sphere of radius 2.1 mm falls with terminal (constant) velocity through a liquid, as shown in Fig. 1.1. constant velocity downwards sphere, radius 2.1 mm weight 7.2 × 10–4 N liquid, density ρ Fig. 1.1 Three forces act on the moving sphere. The weight of the sphere is 7.2 × 10–4 N and the upthrust acting on it is 4.8 × 10–4 N. The viscous force FV acting on the sphere is given by FV = krv where r is the radius of the sphere, v is its velocity and k is a constant. The value of k in SI units is 17.

Read automatically from the paper; the printed page above is exact.