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Two bumper cars are moving towards each other. Car A has amass of 200 kg and is moving at a speed of 4 m/s to the right.Car B has a mass of 175 kg and is moving to the left at aspeed of 6.5 m/s. After the cars collide, Car A is moving to theleft at a speed of 2.5 m/s. How fast, and in what direction, iscar B moving after the collision?

User DarkGhostHunter
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1 Answer

11 votes
11 votes

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?

Step-by-step 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,


\begin{gathered} mu+m^(\prime)u^(\prime)=mv+m^(\prime)v^(\prime) \\ \Rightarrow200*4-175*6.5=-200*2.5+175v^(\prime) \\ \Rightarrow800-1137.5=-500+175v^(\prime) \\ \Rightarrow v^(\prime)=(0.92m)/(s) \end{gathered}

Conclusion

Car B is moving at a velocity 0.92m/s towards the right

User William Whyte
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