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 constant force $$F = 20$$ 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 50 rad s$$^{-1}$$. The value of $$n$$, to the nearest integer, is ________.
[Given: In one complete revolution, the disk rotates by 6.28 rad]