Question

A 5 kg toy truck moves to 2 m/s east , it colllides head-on with a2kg toy car moving 5 m/s moving west . What is the total momentum of the system?

A) kgm/s 30
B) kgm/s 0
C) kgm/s -20
D) non of it

Answer 1

Momentum

eastward = +

westward = -

`\tt P_A=5* 2=10~kg.m/s\\\\P_B=2* 5=-10~kg.m/s`

total momentum:

`\tt P_A+P_B=10-10=0~kg.m/s`