What is the outcome of a collision between two cars at constant speed?

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In a collision between two cars moving towards each other at constant speeds, the conservation of momentum principle is crucial for determining their post-collision speeds. With car 1 at 5 m/s and car 2 at 3 m/s, the total momentum before the collision can be calculated, and depending on whether the cars stick together or not, different outcomes for their speeds can be derived. The confusion arises from the assumption that constant speed implies zero force and impulse, which is incorrect; impulse relates to the change in momentum during the collision. For realistic game design, understanding these principles is essential to simulate accurate motion. Applying these concepts can lead to interesting discoveries in physics.
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I feel so silly for not being able to work this out...

The situation is this - two cars going towards each other. Both cars' mass = 1Kg. The speed of car 1, say, is 5m/s. The speed of car 2, say, is 3 m/s. THE IMPORTANT THING TO NOTE IS THAT BOTH CARS ARE TRAVELLING AT CONSTANT SPEED!

What I'm trying to work out is what their speed is afterwards!

I've looked into the impulse = change in momentum equations but the bit that's confusing me is if the cars are traveling at constant speed, then acceleration =0; thus force is 0... thus impulse = 0? which is obviously wrong but i can't prove it... :(
Using the impulse method, i assume a contact time of 1 s, for simplicity.

N.B I'm trying to design a game with realistic motion but i can't do it... its killing me! Any help will be duly appreciated.
thanks in advance
 
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Hm... is it something I've not done?
 
You needn't pull your hair out by using Newton's equations. Instead, apply the conservation of momentum principle. You will also need to assume that they either stick together after the collision or that kinetic energy is conserved to solve.
 
Yes. Looks like you're seeing the beauty of physics already =D
 

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