1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Car crash collsion

  1. Apr 7, 2008 #1
    Question:
    A 480kg car moving at 14.4m/s hits from behind another car moving at 13.3m/s in the same direction. If the second car has a mass of 570kg and a new speed of 17.9m/s what is the velocity of the first car after collision?

    Since there is a velocity for one car after the collision and the question asks for the other car's velocity after the collison this collision must be elastic.
    Thus
    m1v1 + m2v2 = m1v1f + m2v2f
    480*14.4 + 570*13.3 = 480v1f + 570*17.9
    14493N = 480v1f + 10203N
    4290N = 480v1f
    8.94m/s = v1f


    Is this right?
     
  2. jcsd
  3. Apr 7, 2008 #2
    Looks right to me.
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook