Working out the speed a parked car travels after a moving car hits it

  • Thread starter Thread starter reefcake
  • Start date Start date
  • Tags Tags
    Car Speed
Join the discussion
Registration is free. Start your own thread to ask a follow-up.
2 replies · 3K views
reefcake
Messages
2
Reaction score
0
Hi I'm forensics student and I'm having trouble with this problem as i don't know how to solve it I would really like to to know the method.

Homework Statement


Calculate the speed in ms-1 at which a parked 1840kg "car A" will be traveling once "car B" crashes into it. assuming that "car B" continues to move forward at 8.4ms-1 after the crash.

info on Car A: Mass(m)= 1840kg, Speed(v)=0 ms-1

info on Car B: Mass(m)= 1400kg, Speed(v)= 26.82 ms-1 Momentum(p), 37548 kg-ms-1
ending speed= 8.4ms-1, Ending momentum= 11760 kg-ms-1

Homework Equations


p=mv (conservation momentum)
F=ma (Newtons 2nd law of motion)
A= uv/t (working out acceleration)



Thanks

reefcake
 
Physics news on Phys.org
Welcome to PH.

After the collision, what momentum will Car A have if momentum is really conserved?
 
SammyS said:
Welcome to PH.

After the collision, what momentum will Car A have if momentum is really conserved?

Hi again ;)

yes that is problem as I'm not sure to go about working out as Car B transfers (p)25788kg-ms to car a but Car A is 1840kg, 440 kg heavier. do i divide (p)25788kg-ms (which is the transferred momentum) by 1840kg to get the speed of CarA?

thanks
 
Last edited: