[SOLVED] need help - body in central force-field Hi, I need help for the following issue: A body B is falling freely on a straight line towards a body A, which emits a central force-field. The formula for acceleration is: a(r)=Gm/r^2 I want to derive a formula both for: v(t)=[?] and s(t)=[?] where at t_0=0 the velocity of body B is v(t_0)=0 and distance s(t_0)=0 (the initial moment of body B falling on body A). Thanks for any help in advance, chemical master.