Two cars have a head on collision. Both are traveling at 28 m/s toward each othe. Car A has a mass of 700 kg and car B has a mass of 904kg. What is car B velocity after the impact?

1 answer

use conservation of momentum.
Ma*Va+Mb*Vb=Ma*Va' + Mb*Vb'
28(Ma-Mb)=

well, at this point, you have two unknowns, and you have to stop. You cannot use conservation of energy, you have no basis to assume it was an elastic collision.