Escape Velocity. According to Newton’s law of gravitation, the attractive force between two objects varies inversely as the square of the distances between them. That is, Fg = GM1M2/r2 where M1 and M2 are the masses of the objects, r is the distance between them (center to center), Fg is the attractive force, and G is the constant of proportionality. Consider a projectile of constant mass m being fired vertically from Earth. Let t represent time and y the velocity of the projectile.
(a) Show that the motion of the projectile, under Earth’s gravitational force, is governed by the equation