Determining magnetic field strength as a function of current in Helmholtz coils
DOI:
https://doi.org/10.54355/tbusphys/2.3.2024.0016Keywords:
Helmholtz coils, magnetic field strength, current variation, digital teslameter, calibration factorAbstract
This experiment looks into the relationship between the strength of the magnetic field produced by two Helmholtz coils and the current passing through them. A 100 Ohm, 1.8 A rheostat is used to link the Helmholtz coils to a variable power source (0-20V, 0-5A) while keeping them firmly fastened. The magnetic field at the coils' center is carefully measured by a digital Teslameter equipped with a Hall probe while the current is gradually changed. A digital multimeter with several working modes makes data collecting easier and guarantees accurate results. It is possible to empirically validate theoretical predictions by charting magnetic field strength against current. Strict safety procedures, such as temperature monitoring and safe electrical connections, are followed during the experiment. To guarantee alignment and stability, Helmholtz coils are fastened to a sturdy core assembly utilizing supports, clamps, and rods. The calibration factor and the horizontal flux density as a function of coil current are calculated as part of the setup. The measurement of the angle between the coil axis and the "north/south" direction is made possible by the maximum needle deflection at 4 A.
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