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Mess with your minds: A wind powered craft going faster than a tail wind speed.
electrodacus:
--- Quote from: dunkemhigh on August 30, 2021, 02:00:57 am ---
--- Quote ---the G wheel is breaking
--- End quote ---
OK, to be explicit the G wheel is being braked by the mass of the vehicle acting through the M wheel, yes? In other words, if the M wheel had no grip then the G wheel would again be free to rotate and the vehicle wouldn't move either way?
--- End quote ---
In order to extract any power from G wheel you will need to essentially break so whatever energy you extract from there if it can go 100% to M wheel then that wheel will try to counter the breaking force. You can compare forces in this particular case as gear ratio is 1:1
So since breaking force on the G wheel equal and opposite direction to M wheel the vehicle can not move in any direction but in real world only part of the breaking force will get to M wheel and thus the vehicle will slide backwards assuming the M wheel is the one that slips.
PlainName:
--- Quote ---You can compare forces in this particular case as gear ratio is 1:1
--- End quote ---
Why does it have to be 1:1? Suppose it is 2:1 (or 1:2) - doesn't that make a difference?
--- Quote ---assuming the M wheel is the one that slips
--- End quote ---
Why do we assume that? Let's instead assume the M wheel is grippier than the G wheel.
electrodacus:
--- Quote from: dunkemhigh on August 30, 2021, 02:24:03 am ---
--- Quote ---You can compare forces in this particular case as gear ratio is 1:1
--- End quote ---
Why does it have to be 1:1? Suppose it is 2:1 (or 1:2) - doesn't that make a difference?
--- Quote ---assuming the M wheel is the one that slips
--- End quote ---
Why do we assume that? Let's instead assume the M wheel is grippier than the G wheel.
--- End quote ---
It can be any gear ratio the result will be the same as far as vehicle direction of travel.
2:1 will mean G wheel turns 2x in the same time M will turn only once but since also the force on G is half of that on M (again ideal case) Power at M and G wheel will be the same just opposite direction so vehicle can not move as with no delta in power you can not change the vehicle kinetic energy.
0.5:1 (1:2) means M wheel can spin 2x faster than G wheel but then force at M is half that at G thus again Power applied by both wheels is equal and so no change in vehicle kinetic energy thus vehicle id not moved.
All of the above is based on ideal case in real case power at wheel M will always be slightly lower than at wheel G due to friction and so vehicle will move from right to left if M wheel slips else is G wheel slips then vehicle will stay where it is and energy balance will all be wasted as heat at the interface between the treadmill surface and the wheel.
So if wheel M has perfect grip vehicle remains stationary while energy delta will end up as heat at the G wheel interface with treadmill moving surface.
bdunham7:
Is this all a Monty Python skit? :-DD
electrodacus:
--- Quote from: bdunham7 on August 30, 2021, 02:49:57 am ---Is this all a Monty Python skit? :-DD
--- End quote ---
Just make a test. The energy conservation will not care about your intuition.
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