1. The problem statement, all variables and given/known data I have got a nice problem about free fall. Consider a free-falling bomb vertically down at the target. The movement starts from rest. Bomb is giving sound - speed c= 340 m/s (from friction of air). What is the maximum impact of the bombs to her target (people) to hear sound alive ? 2. Relevant equations I think I will use the equation of free fall and then the general equation for speed and acceleration. s=1/2gt^2 (free fall) s=ct (uniform motion sound) v=gt (current speed uniformly accelerated motion) 3. The attempt at a solution I think the basic premise is sound and that the bomb travels the same path: 1/2gt^2 = ct (calculate t) Then t multiply the acceleration of gravity: v= gt (and it is maximum velocity impact) Of course it is, that the sound must be at the target faster (just) before the bomb. It is right? Thanks very much (and sorry for my English).