When a magnetic field is applied to a current running through a wire, the current moves either up or down depending on the direction of current and magnet. Even through a piece of metal, the magnetic field still affects the beam.
As the negative charge moves up, there is a positive charge moving down to balance it. Once the top and bottom are 'full' the rest of the particles carry on as before since they are attracted by the positive bottom part which balances the magnetic field.
Since there are negative charges at the top, and positive at the bottom, there is voltage across the wire. This can be measured. The Hall effect is the voltage across divided by the current through, which is a resistance.
Measuring this charge is how burglar alarms on a door work. They have a magnet one side and a detector the other side which measures the change in magnetic field.
http://www.sixtysymbols.com/videos/halleffect.htm
No comments:
Post a Comment