(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

One car has twice the mass of a second car, but only half as much kinetic energy. When both cars increase their speed by 5.7 m/s, they then have the same kinetic energy. What were the original speeds of the two cars?

2. Relevant equations

KE=1/2mv^2, where KE equals kinetic energy.

3. The attempt at a solution

Don't know where to start.

Car 1: .5KE=(1/2)(m)(v1^2)

Car 2: KE = (1/2)(.5m)(v2^2)

You can set the 2 equations equal in KE when 5.7 is added to both v1 and v2, but there are still too many variables! I have been stuck on this problem for 2 hours and I am about to go crazy! Please help!

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# Homework Help: Kinetic Energy/Velocity Relationship

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