Force and a collision Two identical masses m are initially a

Force and a collision Two identical masses m are initially at rest, a distance x apart (in the ground frame). A force F, constant in the ground frame, accelerates one of them towards the other until they collide and stick together. What is the mass of the resulting particle? Check that your result is reasonable when x rightarrow 0.

Solution

The mass of the resulting partcle is m+m=2m