How Do Mass and Speed Affect Kinetic Energy in Cars?

AI Thread Summary
The discussion centers on a physics problem involving two cars with different masses and kinetic energies. One car has double the mass of the other but only half the kinetic energy. After both cars increase their speed by 6.0 m/s, they achieve equal kinetic energy. The original speeds of the cars need to be determined using the kinetic energy formula, KE = 0.5mv². Participants suggest setting up equations for the initial and final kinetic energy of each car to solve for their speeds.
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Kinetic Energy and cars... Please help

Homework Statement


One car has twice the mass of a second car, but only half as much kinetic Energy. When both cars increase their speed by 6.0 m/s, they then ave the same kinetic energy. What were the original speeds of the two cars.


Homework Equations


Im not sure but i think its:

KE=.5mvf2-.5mvi2


The Attempt at a Solution



I manipulated the above equation by making KE multiplied by .5 and then removing the .5 from both masses.This however got me no where so could someone please help?
 
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Try writing out the intial and final kinetic energy of each car and then go from there.
 

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