Q.Calculate the acceleration due to gravity at a height of 300 km from the surface of the Earth. (M = $5.98\times10^{24}$ kg, R = 6400 km).

The acceleration due to gravity decreases continuously as height h above a planet's surface increases, following the exact inverse-square relation $g_h=\dfrac{gR^2}{(R+h)^2}$, obtained by simply replacing the surface distance R with the larger distance $(R+h)$ in $g=GM/r^2$. For small altitudes where $h\ll R$, this simplifies (via the binomial approximation) to the widely used linear formula $g_h\approx g\left(1-\dfrac{2h}{R}\right)$, accurate for heights genuinely small compared to the roughly 6400 km radius of the Earth, but increasingly inaccurate at satellite altitudes where the full inverse-square formula must be used instead. …