friday fun space question....
Discussion
Assuming the wheel of the unicycle has inertia, then he will revolve slowly, around their combined centre of mass. As the masses of his legs are not in perfect balance (one goes up, one goes down as the pedals revolve, but one is back and one is fowards) he will also probably jiggle up and down at roughly his pedalling frequency
All good answers.
So yes, assuming the astronaut exited the ISS with a small amount of speed, he will of course continue on this direction as there is no opposing medium/force to decelerate him.
Also yes, rotational movement of his legs would create a wobble.
The initial pedal movement to set the unicycle in motion would have created an equal and opposite reaction force on the feet/legs, due to the inertia of the wheel having to reach a speed from rest. As this force is a distance away from the centre of mass of the astronaut and unicycle as a combined 'system', then this would have created a torque to set a rotational motion in to action. (in a backward roll direction)
Finally, as also mentioned, a gyroscopic torque would be created from the rotating wheel which invokes a force at right angles (under the "right-hand rule", with the thumb giving the direction of this torque). And again as this location of the torque is not acting at the centre of mass, the astronaut would spin ar$e over head (in a cart-wheel direction) - assuming he is putting in some effort to pedal.
Early finish today - have a nice xmas all !
So yes, assuming the astronaut exited the ISS with a small amount of speed, he will of course continue on this direction as there is no opposing medium/force to decelerate him.
Also yes, rotational movement of his legs would create a wobble.
The initial pedal movement to set the unicycle in motion would have created an equal and opposite reaction force on the feet/legs, due to the inertia of the wheel having to reach a speed from rest. As this force is a distance away from the centre of mass of the astronaut and unicycle as a combined 'system', then this would have created a torque to set a rotational motion in to action. (in a backward roll direction)
Finally, as also mentioned, a gyroscopic torque would be created from the rotating wheel which invokes a force at right angles (under the "right-hand rule", with the thumb giving the direction of this torque). And again as this location of the torque is not acting at the centre of mass, the astronaut would spin ar$e over head (in a cart-wheel direction) - assuming he is putting in some effort to pedal.
Early finish today - have a nice xmas all !
Edited by Atomic12C on Friday 21st December 15:22
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