Magnetic Field Strength | Definition & Facts - Britannica

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External Websites

• OpenStax - College Physics 2e - Magnetic Field Strength: Force on a Moving Charge in a Magnetic Field
• West Texas A&M University - What is the strongest magnetic field possible? Is there a limit?
• Nature - The magnetic field strength and the force distance dependency of the magnetically controlled growing rods used for early onset scoliosis
• Pressbooks - Introduction to Physics - Sources Of Magnetic Fields
• IOPscience - Most-likely DCF Estimates of Magnetic Field Strength (PDF)
• Physics LibreTexts - Boundary Conditions on the Magnetic Field Intensity (H)

magnetic field strength physics Ask Anything Also known as: magnetic field intensity, magnetic intensity Written and fact-checked by Britannica Editors Encyclopaedia Britannica's editors oversee subject areas in which they have extensive knowledge, whether from years of experience gained by working on that content or via study for an advanced degree.... Britannica Editors History Britannica AI Ask Anything Table of Contents Table of Contents Ask Anything

magnetic field strength, the part of the magnetic field in a material that arises from an external current and is not intrinsic to the material itself. It is expressed as the vector H and is measured in units of amperes per metre. The definition of H is H = B/μ − M, where B is the magnetic flux density, a measure of the actual magnetic field within a material considered as a concentration of magnetic field lines, or flux, per unit cross-sectional area; μ is the magnetic permeability; and M is the magnetization. The magnetic field H might be thought of as the magnetic field produced by the flow of current in wires and the magnetic field B as the total magnetic field including also the contribution M made by the magnetic properties of the materials in the field. When a current flows in a wire wrapped on a soft-iron cylinder, the magnetizing field H is quite weak, but the actual average magnetic field (B) within the iron may be thousands of times stronger because B is greatly enhanced by the alignment of the iron’s myriad tiny natural atomic magnets in the direction of the field.

The Editors of Encyclopaedia BritannicaThis article was most recently revised and updated by Erik Gregersen.