Hall Effect and Gaussmeters
Once we have determined the Hall Effect for a particular metal or semiconductor, we can then use the Hall Effect voltage to measure the magnetic field (both magnitude and direction). We merely create a standard current through the material and have a voltmeter measure any voltage difference across opposite sides of the material. This voltage difference is then proportional to the magnetic field perpendicular to the current and perpendicular to the sides of the material on which the voltage is being measured.