As a body is projected to a high altitude above the earths
surface, the variation of the acceleration of gravity with respect
to altitude y must be taken into account. Neglecting air
resistance, this acceleration is determined from the formula
a=−g0[R2/(R+y)2], where g0 = 9.81 m/s2 is the constant
gravitational acceleration at sea level, R = 6356 km is the radius
of the earth, and the positive direction is measured upward.
With what velocity does the particle strike the earth...