Helmholtz Coil (additional)

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Item Helmholtz Coil
Item code
Description For Mag. Calibration
Location The University of Texas at Austin
Serial number
Taxonomy GSH640

A Helmholtz coil is a device for producing a region of nearly uniform magnetic field, named after the German physicist Hermann von Helmholtz. It consists of two solenoid electromagnets on the same axis. Besides creating magnetic fields, Helmholtz coils are also used in scientific apparatus to cancel external magnetic fields, such as the Earth's magnetic field. When making magnetic surveys, the operator must know the sensitivity of the Magnetometer. The electric calibrating or Helmholtz Coil is a dual coil ring which is placed around a magnetometer when the sensitivity of the instrument is to be determined. An adaptor clamped around the base of the instrument supports this coil. The unit case contains operating panel with a precision millimeter, reversing switch, fine and coarse regulating rheostats. The current flowing through the coil causes deflections of the system which are read by the instrument telescope. The Helmholtz Coil is a universal coil and can be used for determining sensitivity on either horizontal or vertical instruments. Since it does not depend on the field strength of calibrating magnets, it is accurate and reliable.