If a moving object (object A) hits an object at rest (object B) in a one-dimensional collision and they have the same mass, which one has a negative velocity or a velocity of zero?

The eight ball, which has a mass of m = 0.5 kg, is initially moving with a velocity v = 4.8i m/s. It strikes the six ball inelastically, which has an identical mass and is initially at rest. After the collision the eight ball is deflected by an angle of θ = 23° and the six ball is deflected by an angle of Φ = 29°, as shown in the figure.   (a)  Write an expression for the magnitude of six balls' velocity, in terms of the angles given in the problem and the magnitude of the eight ball's initial velocity, v. (b)  What is the magnitude of the velocity, in meters per second, of the six balls?   (c)  What is the magnitude of the velocity of the eight ball, in meters per second, after the collision?

Two objects, both with a mass of 1.91 kg are sliding across a horizontal, frictionless surface toward each other. If mass 1 has an initial velocity of 3.5 m/s i  and mass 2 has an initial velocity of -2.46 m/s i, what is the change in total kinetic energy if they undergo a perfectly inelastic collision? Assume that total momentum is conserved.

Same situation as before. This time it s a block of mass 1.24 kg sliding with a constant velocity of 4.13 m/s to the north, which collides 100% elastically with a second, stationary block, of mass 3.08 kg, head-on, and rebounds back to the south, eventually colliding 100% elastically with a wall and rebounding northward. It then overtakes the second block, which is still moving north as a result of the first collision. What will be the speeds of the 1.24-kg and 3.08-kg blocks, respectively, after their SECOND collision with one another?   a. 2.63 m/s and 2.02 m/s   b. 3.33 m/s and 0.95 m/s   c. 2.47 m/s and 1.49 m/s   d. 1.84 m/s and 1.22 m/s