I need to learn how to calculate energy requirement to levitate a mass of 5 metric tons travelling at velocities up to 27km/s. The length of the mass is projected to be 20m long and elliptical in sectional shape. The height will be no more than 2.6m with a lateral width 1m wider than the height.

The power source will be onboard. With the answer to this question I can then proceed to design and build a prototype emissionless powerplant that will meet the needed output.

I have no clue what physics are involved with this nor the equations.

My specialist field is civil engineering which means I understand some mathematics but any answer you supply must please explain each step in detail to help me learn about the issues involved. If any use of alternating current is proposed, it impacts on my materials selection and economics with steel fibre reinforced concrete.

If any heat is a byproduct, I need to understand why, to engineer a solution to transmittung, transferring or absorbing it.

I did find a combination of equations on Wikipedia but I don't know how to apply them to find my solutions to these problems.Tesla unit

I am researching a design for a goods transit hypervelocity type system Magway UK using various frictionless methods and, I believe magnetic levitation may be an option in conjunction with centrifugal force.

Once I better understand the theory behind all this I may be able to write a program to automate calculations to mess with variables and plot theoretical OUTCOMES VS OBSERVATIONS. I have a Casio GII calculator and Excel 365 at my disposal only which means it will be BASIC.

  • $\begingroup$ Assume the body is moving at a uniform rate in a perfectly straight line over a curved surface (the earth) in a perfectly northerly direction $\endgroup$
    – Rhodie
    Feb 26, 2020 at 2:49

1 Answer 1


I'm not sure exactly what you are trying to do but it's difficult and probably extremely dangerous.

The kinetic energy of an object with a mass of 5000 kg and a speed of 27000 m/s is more than a Tera Joule. That's a LOT of energy, in the same range as a low yield tactical nuclear weapon.

27 km/s is also VERY fast. The fastest Maglev train I have been on is on Shanghai and tops out at around 430 k/h or about 120 m/s. So you want to increase the current state of the art by a factor of more than 200, and that's no small feat.

In fact, 27km/s is more than 1/3 of the highest speed a human made object has ever achieved and it's higher than escape velocity from earth. Typically these speed records are achieved in space using the gravity of large stellar object as a helper.

It's also more than 23 times the speed of sound in air. If you move an object of that size at that speed in air, you will generate the loudest sonic boom in history and you will turn the air into plasma generating enormous amounts of heat. In other words, you would have to do this in a vacuum and a really good vacuum at that.

That means you need to do this in a tube, which is also tricky since the object has enormous momentum: about 100 million kg m/s. That means it really wants to go straight and you have to apply a massive amount of force to steer it.

Given all these challenges, the levitation energy appears to be the least of your worries, but we can take a swing at it. In theory, levitation doesn't require any energy at all: you could theoretically just do it all with permanent magnets. You only consume (or gain) energy if you move an object in the direction of the magnetic field. As long as you move perpendicular, you are neither gaining or losing energy.

The actual energy consumption will depend on how you create the magnetic fields in the first place and what the geometry your field has. Assuming you can plaster several square meters full of magnets with only a small gap you need a field strength or flux density of about 1 Tesla. Current Neodymium magnets are quite strong and can actually do this.

Paving your track with permanent magnets is going to be expensive or infeasible. So you could use electromagnets. You would only have to magnetize the area of the track where there is currently a object. This will still take a sizable chunk of energy but probably a lot less than you'll need anyway to accelerate and steer the object.


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