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PhysicsFluidViscosityEasy2 minPYQ_2024

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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:

Options:

Answer:

Solution:

Ignoring buoyancy force, we can write terminal velocity as

$m g = 6 π η r v$

$\Rightarrow v \propto \frac{1}{r}$ (as mass is constant)

Now, $\frac{v}{v'} = \frac{r'}{r}$

$As r' = 2 r$

So $v' = \frac{v}{2}$

Stream:JEESubject:PhysicsTopic:FluidSubtopic:Viscosity

⏱ 2mℹ️ Source: PYQ_2024

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