Question

Two cars have a ‘rear end’ collision. A 120 kg Honda moving at 20 m/s strikes a 100 kg Ford moving at 15 m/s. Their bumpers become locked and they continue to move as one mass. What is their final velocity?

Answer 1

Given

Mass of the Honda car, m=120 kg

Velocity of the Honda car, v=20 m/s

Mass of the Ford, m'=100 kg

Velocity of the Ford , v'=15 m/s

To find

The final velocity.

Step-by-step explanation

The combined velocity is V

By conservation of momentum,

`\begin{gathered} mv+m^(\prime)v^(\prime)=(m+m^(\prime))V \\ \Rightarrow120*20+100*15=(120+100)V \\ \Rightarrow V=17.72\text{ m/s} \end{gathered}`

Conclusion

The combined velocity is 17.72 m/s