I am currently trying to work out if two objects, of given mass X and Y, (given in KG) are both travelling toward eachother at Zmps, and collide head on, and come to a complete rest. how do i find the force of each object on impact. Without taking into account air resisitance. I'm aware of the formula F=ma does this then mean simply X*Z= A newtons Y*Z= B Newtons A+B= combined force of two vehicles If so, Given that the two objects are Cars & have a crumple zone of 1.3m how will this affect my calculation. Also, how do i calculate change in momentum, and change in enery of each vehicle? any help appreciated as i am baffled.