# Homework Help: What is the detailed physics of the EMS maglev levitation system

1. Jul 3, 2013

### rosieq1!

1. The problem statement, all variables and given/known data

I have to complete a detailed essay on the physics of an electromagnetic suspension (EMS) Maglev train. Using physics concepts and showing equations i must explain how a) the train levitates, and b) how it is propelled along the guide way.

2. Relevant equations

F=BILsinθ

3. The attempt at a solution

a) I already understand that the EMS system levitates above the guide way using magnetic attraction between electromagnets on the undercarriage and the long-stator ferromagnetic magnets on the guide way. But i am required to give a detailed essay on the physics to a yr 12 standard, i have tried to find how i can explain the physics in more detail then "opposite poles attract". I am thinking that maybe there is some sort of field around the electromagnet that causes it to be attracted to the long-stator ferromagnetic magnet.

b) I understand that a long-stator linear motor is fixed to the underside of the guide way, the stator pack is made of ferromagnetic material and wound with the motor's three-phase windings. To propel the train an AC current is applied to the cable windings, braided into the long-stator pack to produce a 'traveling electromagnetic field' along the guide way. The field draws the train’s electromagnets forwards as one, propelling the train.
What i want to know is if this principle is the same as F=BILsinθ, in that there is a current, a magnetic field and the length is the track (guide way). If the magnetic field runs across the track and the current is directed up out of the track, then there would be a force acting on the train that would propel it forwards.

2. Jul 4, 2013

### Simon Bridge

You mean a magnetic field?
You should look through your course notes on electromagnets and magnetism to see what sort of models are being used ... then describe it in those terms.

It may help to look online for particular types of EMS system, pick one, and describe how it works.
i.e. get a picture and draw the force arrows and field lines in perhaps?

3. Jul 5, 2013

### rosieq1!

thankyou, i'll look up on that and talk about the different fields created by magnets