# Physics

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A car is traveling at 14 m/s. How fast would the car need to go to double its kinetic energy? By what factor does the car's kinetic energy increase if its speed is doubled to 28 m/s?

We only get 3 chances and I'm on my last one before I get the question wrong, help?

• Physics -

KE is proportional to v^2
Or, v is proportional to sqrt KE
so if KE is doubled, v goes up by 1.414

if speed doubled, KE goes up by 4

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