Principle and Working:
When a conductor through which current is flowing, is placed in the magnetic field, a potential difference is generated between two opposite edges of the conductor in the direction mutually perpendicular to both the field and the conductor. This potential developed is Hall voltage & this phenomenon is called Hall effect.
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In the present setup, the crystal mount on PCB is placed perpendicular to the magnetic pole pieces. Magnetic field is produced by electromagnet operated by 0-20V, 5A power supply. Field intensity measured by digital gauss meter with gauss probe. A constant current (0-20mA) is passed through the crystal and induced hall voltage is measured on digital display.