Does a fan spinning at infinite speed move any air?

Cius

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Impossible scenario. Cenrefugal force would also be infinite, meaning no material would be strong enough to do that.
 

Temujin

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Simple answer, yes, yes it does... even one not spinning at infinite speed/at a stand still/0rpm moves air

Now, had the question been does it blow/circulate air... thats a different story, but as for the 'move' question, all objects move air out of their way... the objects mass takes its place
 

johncgalloway

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Impossible scenario. Cenrefugal force would also be infinite, meaning no material would be strong enough to do that.
Wouldn't it be better to say: Highly improbable scenario... no material that we know / can theorise about...
 

SeRpEnT

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Would any matter moving at infinite speed (faster than light then?) remain matter or convert to pure energy?
 

Urist

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Would need to be a circular singularity like you might find in a black hole and the moving air would be the least of our problems?
 

smkungfu

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Hypothetical infinities and rigid mechanical systems gonna get confusing real quick. Why don't you just define an upper limit for the fan speed?
Well he said infinite so I would assume it's the speed of light. So the upper limit will be
299 792 458 m / s.
 

Arksun

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Well he said infinite so I would assume it's the speed of light. So the upper limit will be
299 792 458 m / s.
In my understanding of the theory of general relativity, infinite speed is the speed of light, because when traveling at that speed, time literally stops, meaning that the trip is instant. Only problem with the OP is nothing with mass can reach that speed. If you somehow managed to get the fan to spin close enough to that speed, you would run into a few problems. Aside from slowing down time, velocity also increases mass. An increase in mass requires an increase in propulsion, or in this case, power. As the fan's blades approaches infinite speed (speed of light), the fan itself would approach infinite mass. This is basically a fancy way to say you'll wind up with a black hole.

Also, the speed of light is the universal speed limit. Because of the affect speed has on time, time stops at the universal speed limit. Photons have no mass, so it's basically the only thing that can do that speed, which is why we call the universal speed limit the speed of light.
 

cyberghost47

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In my understanding of the theory of general relativity, infinite speed is the speed of light, because when traveling at that speed, time literally stops, meaning that the trip is instant. Only problem with the OP is nothing with mass can reach that speed. If you somehow managed to get the fan to spin close enough to that speed, you would run into a few problems. Aside from slowing down time, velocity also increases mass. An increase in mass requires an increase in propulsion, or in this case, power. As the fan's blades approaches infinite speed (speed of light), the fan itself would approach infinite mass. This is basically a fancy way to say you'll wind up with a black hole.

Also, the speed of light is the universal speed limit. Because of the affect speed has on time, time stops at the universal speed limit. Photons have no mass, so it's basically the only thing that can do that speed, which is why we call the universal speed limit the speed of light.
Yet it takes light from stars in distant galaxies millions of years to reach our eyes, so the trip is in fact not instant?
 

Moosedrool

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It's pointless to discuss since all laws of physics was voided when you say infinite.

Rather consider unbelievably fast motion: Does a fan where the tip of the blades move near light speed move any air?
 

Arksun

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Yet it takes light from stars in distant galaxies millions of years to reach our eyes, so the trip is in fact not instant?
To the photon, yes it is instant. To an outside observer at 1g gravity and standing still, not instant. Time only slows down for whatever object is traveling at an insane speed.

If you could send a craft with a few people in it moving from the sun to earth at the speed of light, it would take them 8 minutes to get here, but if you could look inside that craft while it's traveling at that speed, you would see the passengers perfectly still and motionless, because to that capsule and the passengers, time has completely stopped. From your perspective the trip took 8 minutes. From their perspective the trip was instant.
 
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