electromagnetism: Quick Facts

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Facts

Also Known As	electromagnetic interaction

Photos and Videos

Two diagrams compare electric fields: on the left, arrows radiate outward from a red sphere with a plus sign, showing the field of a positive charge; on the right, arrows point inward toward a blue sphere with a minus sign, showing the field of a negative charge.

Two diagrams show the magnetic field around a long straight wire carrying current. Panel A presents an end view with concentric circular field lines around the wire, current flowing toward the viewer. Panel B shows a three-dimensional view with the wire angled across the image and circular magnetic field lines surrounding it.

Diagram showing the magnetic force on moving charges: positive and negative charges move along the y-axis in a magnetic field pointing up the z-axis, with force vectors perpendicular to both velocity and field direction.

A diagram showing a magnet being moved upward toward a conducting ring, with magnetic field lines passing through the ring. The induced current in the ring creates a magnetic field that opposes the magnet's approach, illustrating Faraday's and Lenz's laws of electromagnetism.

Diagram of an AC transformer showing a rectangular core with two coils of wire wrapped around opposite sides. The left coil is labeled N1 turns and E1, and the right coil is labeled N2 turns and E2.

Diagram showing a current labeled i charging a capacitor, with side-by-side panels. Each panel displays a blue arrow representing current flowing toward two capacitor plates-one with positive and one with negative charges. Large purple surfaces labeled P and S1 or S2 illustrate different surfaces intersecting the current path, representing Maxwell's displacement current in electromagnetism.

Illustration of Otto von Guericke standing beside his early electrostatic generator, holding a rod with a spherical end near a large mounted disk.

Benjamin Franklin

Understand how the concept of touch changes with the presence of electrons between two objects

Learn about Michael Faraday's and James Clerk Maxwell's discovery of the electromagnetic field and waves

Learn about space expansion and why gravity and electromagnetism are not affected when space expands

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Topics

electromagnetic radiation Coulomb force magnetic force electromagnetic field electricity physical science magnetism electroweak theory matter time light gravity relativity chemical reaction space-time strong force weak interaction energy field

Dig Deeper: More Articles That Discuss This Topic

subatomic particle: Electromagnetism

Key People

Michael Faraday

Michael Faraday

British physicist and chemist

Kelvin, William Thomson, Baron

William Thomson, Baron Kelvin

Scottish engineer, mathematician, and physicist

James Clerk Maxwell

James Clerk Maxwell

Scottish mathematician and physicist

Engraving portrait of Carl Friedrich Gauss wearing a cap and formal 19th-century clothing, with detailed shading around his face and upper body.

Carl Friedrich Gauss

German mathematician

J.J. Thomson

J.J. Thomson

British physicist

André-Marie Ampère

André-Marie Ampère

French physicist

Siméon-Denis Poisson

Siméon-Denis Poisson

French mathematician

Joseph Henry

Joseph Henry

American physicist

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Steven Weinberg

American physicist

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Hans Georg Dehmelt

American physicist

Biot

Jean-Baptiste Biot

French physicist

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George Green

British mathematician

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Sheldon Glashow

American physicist

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Abdus Salam

Pakistani physicist

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Henry Augustus Rowland

American physicist

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Sir Alfred Ewing

British physicist

Nevill F. Mott

Sir Nevill F. Mott

British physicist

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Wolfgang Paul

German physicist

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Wilhelm Eduard Weber

German physicist

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Willis Eugene Lamb, Jr.

American physicist

Italian physicist Guglielmo Marconi at work in the wireless room of his yacht Electra, c. 1920.

All About Physics Quiz

Italian-born physicist Dr. Enrico Fermi draws a diagram at a blackboard with mathematical equations. circa 1950.

Physics and Natural Law