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J5-17. Helmholtz Coils And Hall Probe


To investigate quantitatively the magnetic field of a pair of Helmholtz coils.


Helmholtz coils with power supply, Hall probe with projection slave meter.

Setup Time

5 minutes.




Current is passed through a pair of Helmholtz coils and the magnetic field measured using an azimuthal Hall effect probe. The measured magnetic field value can be displayed by a projection meter slaved to the output of the Hall probe. The field of the Helmholtz coils can be seen to be very uniform over a large volume near the center of the coils. ◙◙Have your students do the calculation showing that spacing the coils at a distance equal to their radius provides the greatest◙volume of nearly uniform field by producing zero gradient in the axial component of the magnetic field at the center of th