JEE Mains · Physics · STD 11 - 9.1 fluid mechanics
A small spherical ball of radius \(r\), falling through a viscous medium of negligible density has terminal velocity ' \(v\) '. Another ball of the same mass but of radius \(2 r\), falling through the same viscous medium will have terminal velocity _______.
- A \(\frac{\mathrm{v}}{2}\)
- B \(\frac{\mathrm{v}}{4}\)
- C \(4 \mathrm{v}\)
- D \(2 \mathrm{v}\)
Answer & Solution
Correct Answer
(A) \(\frac{\mathrm{v}}{2}\)
Step-by-step Solution
Detailed explanation
Since density is negligible hence Buoyancy force will be negligible at terminal velocity. \({Mg}=6 \pi \eta \mathrm{rv}\) \(\mathrm{V} \propto \frac{1}{\mathrm{r}} \quad\) (as mass is constant) Now,…
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