Maglev Trains And The Technology Behind Them Essay
Magnetism is a phenomenon that occurs when a moving charge exerts a force on other moving charges. The magnetic force caused by these moving charges sets up a field which in turn exerts a force on other moving charges. This magnetic field is found to be perpendicular to the velocity of the current. The force of the field decays with distance from the charge. Most magnets we come across are weak permanent magnets, such as fridge magnets and door catches. A permanent magnet is a material that is naturally magnetic, they set up magnetic fields by electrons circling an atom setting up magnetic fields. They are based on …show more content…
The repulsive force between magnets with like poles facing explains how permanent magnets can be used to provide a levitating and thrust force to the train.
Magnet Strength ===============
We know that magnets have a north and south pole and if we bring them together they will repel each other. We can see this effect in the picture below with the area between the two magnets having the iron filings being repelled away from the area in between the two magnets.
We can use this theory to determine the strength of repulsion. We use the following formulas. =====================================================================
The magnetic flux density is another word for the strength of the magnetic field. Lines of magnetic force of flux are used to describe the shape of a magnetic field near a magnet or solenoid (a long coil through which current is flowing, establishing a magnetic field). The density of the lines of force increase in proportion to the field strength. It can be calculated by using the equation
where B is the flux density O is the flux and A is the cross sectional area