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Old 11-02-2012, 03:28 PM   #12 (permalink)
PaleMelanesian
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Quote:
Originally Posted by JRMichler View Post
But, at 60 MPH, that is the difference between 55 MPH and 65 MPH airspeed depending whether it's a tailwind or a headwind. The difference in aerodynamic drag is proportional to the square of the airspeed, or 40%.
Correct. In this case, the two airspeeds are 55 mph and 65 mph.

65^2 = 4225
55^2 = 3025
4225/3025 = 1.397, or about 40% higher.

Or to put it another way, 10 mph over 55 is an 18% difference. 1.18*1.18 = 1.39, or again almost 40%.
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