SSC JE Mechanical Engineering 2018 Set 5 Paper

In free vortex motion, the tangential velocity of the water particles is proportional to $\frac{1}{\mathit{r}}$
In a purely circulatory (free vortex flow) motion, the tangential velocity can be written as
${\mathit{\upsilon }}_{\mathit{\theta }}=\frac{\mathrm{Circulation}\mathrm{constant}}{\mathit{r}}$