Helmholtz Coils And Hall Probe

Purpose

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

Equipment

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

 

Setup Time

5 min.
 

    Images

    J5-17

    Description

    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