A sphere of density ρ s and diameter D is dropped from rest in a fluid of

Question:

A sphere of density ρ s and diameter D is dropped from rest in a fluid of density ρ and viscosity μ. Assuming a constant drag coefficient o Cd, derive a differential equation for the fall velocity V(t) and show that the solution is Where S = ρ s /ρ is the specific gravity of the sphere material.

A sphere of density ρ s and diameter D