Consider a 20 kg uniform circular disk of radius 0.2 m. It is pin supported at its center and is at rest initially. The disk is acted upon by a…

Consider a $\displaystyle 20$ kg uniform circular disk of radius $\displaystyle 0.2$ m. It is pin supported at its center and is at rest initially. The disk is acted upon by a constant force $\displaystyle \mathrm{F}=20 \mathrm{~N}$ through a massless string wrapped around its periphery as shown in the figure. Suppose the disk makes n number of revolutions to attain an angular speed of $\displaystyle 50 \mathrm{rad} \mathrm{s}^{-1}$. The value of n, to the nearest integer, is \_\_\_\_. [Given : In one complete revolution, the disk rotates by $\displaystyle 6.28$ rad]