What is the Highest RPM in the Universe?

In summary: No, a brushless stepper motor. This illustrates the problem with the question, because RPM on its own has no limit (as the revolving system decreases in radius). Using a radius about one meter, the speed of light limits us to an RPM of about 18 billion, so that is a safe upper limit.My semi-educated guess is that the fastest that anyone will ever likely run across in reality would be a black hole. Since the angular momentum of the remains of the original star is conserved, those suckers can spin.Yeah danger, that's probably a very close guess, although I suspect a microscopic black would be even faster.Noone else knows
  • #1
fedorfan
115
0
Does anyone know what the highest rpm in the universe is?
 
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  • #2
RPM? are you talking about tires or computers or what

if its speed related don't doubt the power of c
 
  • #3
Does anyone know what the highest rpm in the universe is?

No, but John Wheeler would jokingly discuss the maximum upper limit on horsepower (about 10^64), an engine with which would instantly rip itself into a black hole:biggrin: .
 
  • #4
My best guess would be a turbocharger at like 180,000 rpm. I guess the universal speed limit would be the speed of light. Also, I am talking about whatever is rotating the fastest. Not pkanets or something though, I mean revolutions per minute, not year.
 
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  • #5
fedorfan said:
My best guess would be a turbocharger at like 180,000 rpm.

This illustrates the problem with the question, because RPM on its own has no limit (as the revolving system decreases in radius). Using a radius about one meter, the speed of light limits us to an RPM of about 18 billion, so that is a safe upper limit.
 
  • #6
My semi-educated guess is that the fastest that anyone will ever likely run across in reality would be a black hole. Since the angular momentum of the remains of the original star is conserved, those suckers can spin.
 
  • #7
Yeah danger, that's probably a very close guess, although I suspect a microscopic black would be even faster.
 
  • #8
Noone else knows anything?
 
  • #9
flagellum

I'd say it is the flagellum at up to 17,000 rpm...if you look at a figure of it you'll be pretty amazed at it's complexity and sophistication
 
  • #10
fedorfan said:
My best guess would be a turbocharger at like 180,000 rpm. I guess the universal speed limit would be the speed of light. Also, I am talking about whatever is rotating the fastest. Not pkanets or something though, I mean revolutions per minute, not year.
Electrons around nuclei in atoms good enough candidates?
 
  • #11
To start with, that would be revolving, not rotating... but it doesn't count anyhow. As for the electron spin component, it isn't really spin. I think that you pretty much have to stick with macroscopic phenomena.
 
  • #14
How could one convince one's self that Dyson's little motor is running at such a high rpm? Even with an oscope, how would one know that the oscope isn't simply picking up "fake" electronic signals from the control circuit? I don't believe that I can hear such a high pitch. Maybe some angular momentum test?
 
  • #15
The maximum RPM in the universe is dependent on the radius of the spinning object.

The formula for calculating velocity of the outer edge of the "wheel" using RPM is:

[tex]\upsilon=C*RPM[/tex]

Therefore:

[tex]RPM=\frac{\upsilon}{C}[/tex]

Plugging the speed of light in for velocity (and making it an inequality to show that it has to be less than c):

[tex]RPM<\frac{c}{C}[/tex]

So the maximum RPM of an object is the speed of light divided by the object's circumference. That means the smaller the object, the faster it can spin.
 
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  • #16
Superstring said:
So the maximum RPM of an object is the speed of light divided by the object's circumference. That means the smaller the object, the faster it can spin.

Which brings us back to black holes...
 
  • #17
Superstring said:
The maximum RPM in the universe is dependent on the radius of the spinning object.

The formula for calculating velocity of the outer edge of the "wheel" using RPM is:

[tex]\upsilon=C*RPM[/tex]

Therefore:

[tex]RPM=\frac{\upsilon}{C}[/tex]

Plugging the speed of light in for velocity (and making it an inequality to show that it has to be less than c):

[tex]RPM<\frac{c}{C}[/tex]

So the maximum RPM of an object is the speed of light divided by the object's circumference. That means the smaller the object, the faster it can spin.
Well, actually
[tex]\omega < \frac{c}{r}[/tex]
and convert to revolutions per minute. (RPM is a unit, it sows confusion to try to use it as a variable)

I got
[tex]\omega < \frac{2.86\times 10^9\,\mathrm{m}}{r}\cdot\frac{\mathrm{rev}}{\mathrm{min}}[/tex]
so... for something with radius equal to the Planck length, [itex]1.77\times 10^{44}[/itex] revolutions per minute? (If such a thing could exist, of course)
 
  • #19
:uhh:
drboylecj said:

Compared to conventional motors, which use carbon brushes that spark to create the rotations, the DDM uses a a stator that creates a strong electromechanical field, which is then switched digitally using an on-board microprocessor. The motor never actually touches the rotors.
You mean a brushless stepper motor?? What will he invent next??:uhh:
 
  • #20
Hi. I just signed up because i was google-ing for the highest recorded rpm for an electric motor and happen to find this forum.

That 1,000,000 rpm motor is pretty amazing.

I come from a hobby world where we use fa-130 size motors (about the radius of a nickle and about an inch in length) running on 2.4 to 3 volts. Most of the aftermarket motors for this hobby are made in china or the philippines and claim excessively high numbers anywhere from 68,000 to 500,000. One of them claimed 1,200,000 rpm. All these are supposedly tested at 3 volts and with no weight on the motor axle. I don't know what testing equipment they used on these motors for such numbers, but I'm more than positive that most of these are highly inaccurate.

I did a little math considering one of the faster cars going 60 mph and plugged in the wheel size and gear ratio to find out that some of these motors do about 60,000 rpm under load, so i can see the same motor, free of load, doing at least 100,000 rpm.

I'm not sure about this, but i think high end slot car drag motors can go even higher, especially given the voltage pushed into those things. Or maybe they just have severally intense gear ratios. I don't know.

To come to a conclusion, i just wanted to point out that 100,000 rpm is a very easily achievable number for a small electric motor, so i am not surprised to hear about that 1 million rpm motor, although i was kind of hoping someone had already pushed the limit higher...oh say to 1,500,000.
 
  • #21
The highest RPM would be that at which the stress at the circumference would equal the elastic strength of the material .
 
  • #23
i know two neutron stars rotating around each other can go almost the speed of light at the second of collision
http://www.haydenplanetarium.org/resources/ava/stars/S0606neutcoll
 
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  • #24
I work in the dental industry and am told the turbines in dental drills rotate between 300000 and 450000 rpm. They are turbines in the head of the drill that are driven by air pressure of between 30 & 45 psi.
 
  • #25
tehno said:
Electrons around nuclei in atoms good enough candidates?
When an electron is in a 'bound state' as it is when part of an atom, its position is not defined well enough to assign it an actual velocity - angular or linear. I don't think you can treat is in this classical way.
 
  • #26
1 = I have no idea of the highest RPM in man made technology.
2 = I don't know the highest existing RPM in nature (the universe) but I think is will be higher then 1

I will focus my answer on the absolute limit: the highest possible according to physics limits.

Speed of the outer edge of a rotating object must be high. Since speed has an upper limit c we must make the object smaller and smaller to get a higher RPM.

That's where the trouble starts: as pointed outbefore, the concept of RPM doesn't apply to subatomic objects.

Another way to look at this limit is to find out what maximum force is needed to keep a rotating object from breaking up. This could give an upper limit but, I'm not sure yet.
 

What is the Highest RPM in the Universe?

The highest RPM (revolutions per minute) in the universe is difficult to determine, as the universe is constantly expanding and changing. However, scientists have measured some incredibly high speeds in various celestial bodies and events.

What is the fastest rotating object in the universe?

The fastest rotating object in the universe that has been measured is the pulsar PSR J1748-2446ad, with a rotational speed of 716 times per second. This is equivalent to a speed of 43,000 RPM.

Can anything in the universe rotate faster than the speed of light?

According to Einstein's theory of relativity, nothing can travel faster than the speed of light. Therefore, it is not possible for any object in the universe to rotate faster than the speed of light.

How do scientists measure the RPM of celestial bodies?

Scientists use various methods to measure the RPM of celestial bodies, such as using telescopes to observe the rotational speed of planets and stars, or analyzing the frequency of electromagnetic radiation emitted by pulsars.

Could there be a celestial body with a higher RPM than anything we have measured so far?

As the universe is vast and constantly expanding, it is possible that there are celestial bodies with higher RPMs than anything we have measured so far. However, these objects may be difficult to detect and measure due to their distance and other factors.

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