Gravitation

Consider a star of mass m₂ kg revolving in a circular orbit around another star of mass m₁ kg with m₁ \gg m₂. The heavier star slowly acquires mass from the lighter star at a constant rate of $\gamma$ kg/s. In this transfer process, there is no other loss of mass. If the separation between the centers of the stars is r, then its relative rate of change $\frac{1}{r}\frac{dr}{dt}$ (in s⁻¹) is given by: