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Old 07-09-2008, 12:55 PM   #26 (permalink)
spyderbite9001
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Join Date: Jul 2008
Location: Colorado Springs
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Vic - '08 Honda Civic EX
90 day: 32.43 mpg (US)

ZED - '11 Honda CR-Z EX
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Quote:
Originally Posted by PA32R View Post
Though it doesn't change your point, air resistance doesn't increase exponentially with speed: r=ce^(ks), it increases as a power of speed: r=ks^2. Here, r is resistance, c and k constants, s is speed.

Misuse of "exponentially" is a pet peeve of mine, sorry.

Sorry to burst ur bubble man, but your looking at the wrong equation. For air resistance yes, it is a function of the square of your velocity (v^2) however, when we talk about gas mileage we should be more concerned with the power req'd to gain/maintain the objective velocity. To calculate the req'd force or power we look at the equation

Power = Force Drag * V supposing that
Force Drag = (1/2)*density fluid*(v^3)*area*drag coefficient

and therefore the growth in power needed, which directly translates to gas mileage, is in fact, exponential.

Reference: Drag (physics) - Wikipedia, the free encyclopedia
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