A particle of mass m is under the influence of the gravitational field of a body of mass M (>> m). The particle is moving in a circular orbit of radius r0 with time period T0 around the mass M. Then, the particle is subjected to an additional central force, corresponding to the potential energy Vc(r) = mα/r3, where α is a positive constant of suitable dimensions and r is the distance from the center of the orbit. If the particle moves in the same circular orbit of radius r0 in the combined gravitational potential due to M and Vc(r), but with a new time period T1, then \(\left(T_{1}^{2}-T_{0}^{2}\right) / T_{1}^{2}\) is given by
[G is the gravitational constant.]
1
\(\frac{3 \alpha}{G M r_{0}^{2}}\)
2
\(\frac{\alpha}{2 G M r_{0}^{2}}\)
3
\(\frac{\alpha}{G M r_{0}^{2}}\)
4
\(\frac{2 a}{G M_{0}^{2}}\)