WBJEE · Physics · Mechanical Properties of Fluids
A small metal sphere of radius \(a\) is falling with a velocity \(v\) through a vertical column of a viscous liquid. If the coefficient of viscosity of the liquid is \(\eta\), then the sphere encounters an opposing force of
- A \(6 \pi \eta a^{2} \mathrm{v}\)
- B \(\frac{6 \mathrm{\eta v}}{\mathrm{\pi a}}\)
- C \(6\pi \eta av\)
- D \(\frac{\pi \eta V}{6 a^{3}}\)
Answer & Solution
Correct Answer
(C) \(6\pi \eta av\)
Step-by-step Solution
Detailed explanation
Stokes established that if a sphere of radius a moves with velocity \(v\) through a fluid of viscosily Coefficient \(\mu\) the viscous force opposing the motion of thy sphere is \(F=6\pi \eta a v\)
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