Solving the Problem of A & B Collision: Acceleration & Force

[aki667]

Im confuse in this problem, please help me because I am having a hard time in solving this problem. The problem goes like this:A cart of A of mass 2.0[kg] which is moving at a speed of 7.0]m/s] on a horizontal floor collides with the object B of mass 5.0[kg] which is standing still on the floor. After that, A and B are united and start sliding. There is no friction between cart and floor and coefficient of sliding friction between cart and floor and the coefficient of sliding friction between B and floor is 0.20. Set the acceleration by gravity to 9.8[m/s²].

1. Find the speed of the object immidiately after collision.

I have solved the speed of object after the collision and i get 2.0 m/s

2. By solving the equation of motion find the acceleration and force acting between A and B.

i can't solve the 2nd part, how can i get the acceleration?

 

[Doc Al]

I suspect that there is friction between the object and floor, but not between the cart and the floor. If so, compute the net force acting on the "cart+object" system after the collision. Then analyze the forces acting on each separately.

Use Newton's 2nd law.