before colliding, the momentum of block a is -100 kg*m/s and block b is -150 kg*m/s. after, block a has a momentum of -200 kg*m/s. what is the momentum of block b afterwards?

You want to move a heavy box with mass 30.0 kg across a carpeted floor. you pull hard on one of the edges of the box at an angle 30∘ above the horizontal with a force of magnitude 240 n, causing the box to move horizontally. the force of friction between the moving box and the floor has magnitude 41.5 n . what is the box's acceleration just after it begins to move