As per the theory of conservation of energy
\(-\frac{ GM_em }{ R_e} + \frac{1}{2}m\bigg(\frac{1}{3}\sqrt{\frac{2Gm_e}{R_e)}}\bigg)^2 = - \frac{GM_em}{R_e+h}\)
- \(-\frac{GM_em}{R_e} + \frac{GM_em}{9R_e} = -\frac{GM_em}{R_e+h}\)
\(\frac{8}{9R_e} = \frac{1}{R_e+h}\)
Therefore, the maximum height attained by the body will be:
\(⇒ h = \frac{R_e}{8}\)
= \(\frac{6400}{8}\)
= \(800\) \(km\)

In mechanics, the universal force of attraction acting between all matter is known as Gravity, also called gravitation, . It is the weakest known force in nature.
According to Newton’s law of gravitation, “Every particle in the universe attracts every other particle with a force whose magnitude is,
On combining equations (1) and (2) we get,
F ∝ M1M2/r2
F = G × [M1M2]/r2 . . . . (7)
Or, f(r) = GM1M2/r2
The dimension formula of G is [M-1L3T-2].