A football player runs to the north at a speed of 8 m/s. He catches a ball and keeps running. What type of collision was this?

Question

anonymous · Answer

two dear run toward each other . one deer has a mass of 20kg and runs west with a speed of 5 m/s, while the other has a mass of 30 kg and runs east with a speed of 4 m/s. what is the total momentum of the system made up of two deer?

a. 20 kg.m/s east
b.220kg.m/s west
c.20 kg.m/s west 
d. 220 kg.m/s east

anonymous · Answer

the collision is perfectly plastic(inelastic)

anonymous · Answer

as after collision both ball and the player move with the same speed then speed of the ball is equal to speed of footballer after catching,
hence after velocities are equal hence it is perfectly plastic(inelastic) collision.

anonymous · Answer

i think total momentum will be change in momentum
taking east direction as +ve and west direction as -ve 
change in momentum=$$m _{1} v _{1} - m _{2} v _{2}$$
                                  =-100+120=+20
therefore ans is 20Nm/s east

anonymous · Answer

sorry its kg and not N