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Old 07-31-20, 02:45 PM
  #16  
Pop N Wood
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Originally Posted by livedarklions
We know that the max speed is well above 100 mph because people can do much better than that on earth when they ride behind a dragster: https://www.npr.org/2018/09/18/64922...w-world-record

So, in a vacuum, this should be even faster. Also, while everything is 1/6 earth weight, your legs will be able to put out the same force as they did on earth, so let's start the bidding on top speed.

I'll start the bidding at approximately 3x earth max, or about 567 MPH. Let's make that the over/under. If you think it's more or less, why?
Not applicable. The dragster is creating a vacuum so the cyclist is getting a boost from the air pressure behind her.

Remove the person from the equation so you don't need to worry about losses of flexing the space suit. Instead assume some max wattage motor. The real work left is computing the rolling resistance of the tires, bearings and drive train. Would need a lot of gearing so losses could be substantial. Subtract some losses for frame flexing due to the irregular pedal motion and vibration due to imperfectly balanced wheels. Add a factor for the bearing grease becoming more viscous and clearances shrinking with temperature.

Max speed will be where these frictional losses equal assumed power output.

Would have to think about the effect of gravity on the process. Level tarmac so assumed no change in potential energy. Force equal mass, not weight, thus times acceleration so the reduced gravity has no real affect on top speed. With less normal force there would be less traction, but with only a half horsepower or so that may not matter either.

In all honesty I think energy losses flexing the suit would be the limiting factor.

Won't break 100 mph. Hell, in suit probably won't hit half of that.

Last edited by Pop N Wood; 07-31-20 at 02:55 PM.
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