Two spherical bodies of masses \(M\) and \(5M\) and radii \(R\) and \(2R\) are released in free space with initial separation between their centres equal to \(12R.\) If they attract each other due to gravitational force only, then the distance covered by the smaller body before the collision is:

A spherical planet has a mass \(M_p\) and diameter \(D_p\)${\mathrm{}}_{}$. A particle of mass \(m\) falling freely near the surface of this planet will experience acceleration due to gravity equal to:
1. \(\frac{4GM_pm}{D_p^2}\)
2. \(\frac{4GM_p}{D_p^2}\)
3. \(\frac{GM_pm}{D_p^2}\)
4. \(\frac{GM_p}{D_p^2}\)