Before colliding, the momentum of block a is +15.0 kg m/s. after, block a has a momentum -12.0 kg*m/s. what is the momentum of block b afterwards

The momentum of block B = 27 Kg m/s

Explanation:

Given,

The initial momentum of block A, MU = 15 Kg m/s

The final momentum of block A, MV = -12 Kg m/s

Consider the block B is initially at rest.

Therefore, the initial momentum of block B, mu = 0

According to the laws of conservation of linear momentum, the momentum of the body before impact is equal to the momentum of the body after impact.

                                MU + mu = MV + mv

                                15  +  (0) = (-12) + mv

                                         mv = 15 + 12

                                              =  27 Kg m/s

Hence, the momentum of the block B after impact is, mv = 27 Kg m/s

the displacement produced by the body.  

the amount of force subjected to the body.  

the angle between the direction of force and displacement

it doesn't. it was imagined up in the middle ages.