Posted by Chris on .
two cars, one with mass m1=1000kg and the other with mass m2= 4000kg crash in an intersection. Before the crash, car m1 was headed east with a speed of v1i= 25 m/s and the car m2 was headed north with a speed of v2i= 10m/s. After the crash, the cars stick together. what is the speed of the 2car wreck after the collision and with what angle does it leave the crash point?

Energy and momentum Physics 
drwls,
The vector sum of the momenta of the two cars before collision equals the momentum of the combined cars after collision.
By solving the momentum conservation equations for two perpendicular axes, you can solve for both final speed and angle.
We will happily critique your work, if needed.