Which car was going faster before the collision? Solving for momentum in 2D

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SUMMARY

The discussion focuses on solving a momentum problem involving two cars of identical mass colliding at an intersection. The cars lock together and move at an angle of 22 degrees north of east after the collision. The key equation used is the conservation of momentum: m1v1i + m2v2i = m1v1f + m2v2f. The conclusion drawn is that the car traveling east was moving faster prior to the collision, as indicated by the final velocity vector's angle.

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So we've just finished our unit on Momentum and Energy in our grade 12 Physics class and today we were given a basic assignment that is to help us think "out-side" the box of typical questions. This particular question has me going insane...I just can't make the connection as to what to do.

The question is:

Two cars of identical mass are approaching the same intersection, one from the south and one from the west. They reach the intersection at the same time and collide. The cars lock together and move away at an angle of [East 22 degrees North]. Which car was going faster before the collision? Explain your reasoning and include all calculations.

Normally with a question like this, I'd be fine trying to solve it with all of the given variables and such (Using the m1v1i + m2v2i = m1v1f + m2v2f equation), but since this gives almost no information, I am at a loss as to how to solve it. Using logic, I know that the car traveling to the east is the one traveling faster since the final vector is going 68 degrees east, while only going 22 degrees north. How do I answer that using algebra with so little specific information? Any sort of help to point me in the right direction would be awesome...
 
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Try breaking up the final velocity into components. How can you relate them to the whole / each other? How does that relate to the initial conditions?
 
Ahhh yes. That would make sense...I should have thought of that. :\

Thanks, I'll give it a go. :)
 
I think one of the hardest parts of physics (and science in general) is making the connection / transition between the concepts and the equations. I'd say, most people can do one OR the other; either the math, or the ideas - but its a lot harder to be able to combine the two, and find one from the other.

Good luck, Cheers!
 

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