I Conservation of angular momentum -- spinning a bicycle wheel in space

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In a frictionless environment, a bicycle wheel in space will not stop rotating unless acted upon by an external force. The conservation of angular momentum remains intact as the wheel's friction with the axle causes both to eventually rotate at the same rate, rather than stopping completely. If the wheel is mounted on a non-rotating bike, the torque will cause the bike to rotate, conserving the total angular momentum of the system. Thus, the initial assertion that angular momentum is violated is incorrect. The system continues to exhibit conservation principles as long as no external forces intervene.
abdossamad2003
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Suppose we have a rotating body like a bicycle wheel in space away from gravity. This body stops after a while due to friction between the wheel and wheel axles. Is not the conservation of angular momentum violated?
 
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If it's just the wheel, then there's no axle exerting friction and the wheel will rotate without slowing forever. If it is mounted on a non-rotating bike, then the bike will take up the torque and begin rotating, conserving angular momentum.
 
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abdossamad2003 said:
Suppose we have a rotating body like a bicycle wheel in space away from gravity. This body stops after a while due to friction between the wheel and wheel axles. Is not the conservation of angular momentum violated?
You are wrong to say that the body stops. As per @Halc's answer, the wheel slows and the axle spins up until both are rotating at the same rate. Then the wheel and axle continue to spin eternally, at rest with respect to each other.
 

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