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zeropointbug · 05:09 PM

It's actually more than the square of the speed increase. The wind drag is the square.

You have to take into account:

-wind drag
-tire resistance
-drive train resistance

So, for example going from 40mph to 80mph, the motor needs twice the torque, AND twice the speed to overcome the wind drag. Also, the whole drivetrain resistance goes up linearly, so the wind drag, which goes up as a curve with speed, and resistance, which goes up as a straight line. Add them together and it's more than the square of the speed increase. It becomes less apparent the faster you go.

Likewise, at low speeds, tire and drivetrain resistance is the major player at those speeds. Wind resistance is minimal, as it goes down drastically as you lower speed.

	(#13)
zeropointbug Z-Pinch racer Offline Posts: 3,141 Join Date: Nov 2006 Location: SK, Canada	04.17.2007, 04:47 PM It's actually more than the square of the speed increase. The wind drag is the square. You have to take into account: -wind drag -tire resistance -drive train resistance So, for example going from 40mph to 80mph, the motor needs twice the torque, AND twice the speed to overcome the wind drag. Also, the whole drivetrain resistance goes up linearly, so the wind drag, which goes up as a curve with speed, and resistance, which goes up as a straight line. Add them together and it's more than the square of the speed increase. It becomes less apparent the faster you go. Likewise, at low speeds, tire and drivetrain resistance is the major player at those speeds. Wind resistance is minimal, as it goes down drastically as you lower speed. “The modern astrophysical concept that ascribes the sun’s energy to thermonuclear reactions deep in the solar interior is contradicted by nearly every observable aspect of the sun.” —Ralph E. Juergens Last edited by zeropointbug; 04.17.2007 at 05:09 PM.