# What speeds could a maglev train reach in a vaccum?

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1. Feb 15, 2017

### Rebekah Barker

What would happen?

2. Feb 15, 2017

### Staff: Mentor

What are your thoughts? What do you think would happen and why?

3. Feb 15, 2017

### Staff: Mentor

I think you mean more than a vacuum.

If you had maglev in a frictionless environment (vacuum),
and weightless (no gravity to overcome),
and a perfectly straight and infinitely long maglev rail,
and infinite time and distance to accelerate in,
and superconducting rails so that the electric driving wave does not decay,
then the maglev vehicle could travel as fast as the EM electric wave travels in the rail. Something on the order of 0..6-0.8 times light speed.

Even with that long list, there are probably even more qualifiers that I didn't think of.

4. Feb 15, 2017

### Inventive

Although I do not know how to calculate that right off the bat, I am curious about this question too. I am seeing a near frictionless environment when the train is in the vacuum. Can a vacuum in a finite space be thought of as a vector field which might influence the trains speed. Could there be a "negative vacuum" that could slow it down on demand?

5. Feb 15, 2017

### Rebekah Barker

Well the top speed a maglev train has reached is around 600km/h so as there is near to no friction I think it could reach speeds of thousands of km/h. It would be extremely efficient but i don't think anything can 100% efficient. It would be able to reach extremely high speeds but i'm not sure what the limit would be. Yet it wouldn't be very convenient for a mode of transport haha.

6. Feb 15, 2017

### OmCheeto

I come up with ≈15,700 mph, which is ≈25,200 km/hr.

Many assumptions, of course.

Fun thought experiment!