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Old 08-10-2019, 05:52 PM   #46 (permalink)
RedDevil
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Join Date: Dec 2012
Location: Nieuwegein, the Netherlands
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Red Devil - '11 Honda Insight Elegance
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90 day: 51.36 mpg (US)

It - '09 Hyundai I10 Active Cool
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Quote:
Originally Posted by Vman455 View Post
-Scaling up the body will increase its mass, which will also increase its rolling resistance
Of course. But not 65 times as much, and not linear to weight. Bigger wheels, relatively less contact area in the moving parts does reduce friction.
Quote:
Originally Posted by Vman455 View Post
-energy required correlates to the cube of velocity for aerodynamic drag force
NO!
We are talking energy efficiency here. To move an object twice as fast the drag quadruples (as it is squared) and the distance covered doubles (as it is linear with speed). So you need 8 times as much power, but you cover twice the distance, hence the economy only suffers to the square.

Call them liars or accept their claim expecting they know their math better than we do. I hinge on the latter.
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