Given
Car A has a mass of m=200 kg and is moving at a speed of u=4 m/s to the right.
Car B has a mass of m'=175 kg and is moving to the left at a speed of u'=6.5 m/s.
After the cars collide, Car A is moving to the left at a speed of v=2.5 m/s
To find
How fast, and in what direction, is car B moving after the collision?
Explanation
Let the velocity of car B after collision be v'
Let us consider the direction towards right to be positive
By conservation of momentum before and after collision,
[tex]\begin{gathered} mu+m^{\prime}u^{\prime}=mv+m^{\prime}v^{\prime} \\ \Rightarrow200\times4-175\times6.5=-200\times2.5+175v^{\prime} \\ \Rightarrow800-1137.5=-500+175v^{\prime} \\ \Rightarrow v^{\prime}=\frac{0.92m}{s} \end{gathered}[/tex]Conclusion
Car B is moving at a velocity 0.92m/s towards the right
