Comments by "John Gottschalk" (@JohnGottschalk) on "A Physics Prof Bet Me $10,000 I'm Wrong" video.

So why don't we have chain-driven propellors on bikes. If you can just pedal them up to speed, then wouldn't the wheels and the propellor do the rest? And you just have to brake? They say it could even go forward in a head wind right? (assuming the initial speed is fast enough, I suppose) so if you were pedaling (or powering in some other way) what's stopping you getting up to that speed and making use of this?
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