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: Inelastic collision car

  1. Dec 7, 2008 #1
    1. The problem statement, all variables and given/known data

    A 1200 kg car moving at 88 km/h collides with a 7600 kg truck moving in the same direction at 65 km/h. The two stick together, continuing in their original direction at 68 km/h. Determine the kinetic energy of the center of mass of the (car + truck) system. Determine the internal energy of the (car + truck) system before the collision. Determine the internal energy of the (car + truck) system after the collision.

    2. Relevant equations

    m1v1 + m2v2 = (m1 + m2)vf

    Kinetic energy of a system is K = Kcm + Kint

    K = 1/2mv2

    3. The attempt at a solution

    88 km/h converted to 24.4444 m/s
    65 km/h converted to 18.0556 m/s
  2. jcsd
  3. Dec 7, 2008 #2


    User Avatar
    Homework Helper

    You'd need to find the velocity of the (car+truck) system after collision to get the kinetic energy.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook