posted by Hannah .
1)A 1180-kg van, stopped at a traffic light, is hit directly in the rear by a 753-kg car traveling with a velocity of +1.81 m/s. Assume that the transmission of the van is in neutral, the brakes are not being applied, and the collision is elastic. What is the final velocity of (a) the car and (b) the van?
I was going to use the equation
m1v1 + m2v2 / m1+m2 but then i realized that I have to find the velocity for both of the cars and now I am confused.