A leaf is caught in a whirlpool. At a given instant, the leaf is at a distance of 120 m from the center of the whirlpool. The whirlpool can be described by the following velocity distribution: $V_r=-\bigg(\frac{60\times10^3}{2xr}\bigg)$ m/s and $V_0=\frac{300\times10^3}{2xr}$ m/s, where r (in meters) is the distance from the center of the whirlpool. What will be the distance of the leaf from the center when it has moved through half a revolution?