Of Car Crashes and Snickers Bars

Pop quiz, hotshot. Using the caloric energy content of a candy bar (e.g. Snickers, at 250 food calories), what is the kinetic energy of a two-ton behemoth SUV traveling at about 70 mph? A first-order approximation is fine — no need to worry about more than one significant digit.

Got it? Think of your number and then proceed to the analysis.
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