Photon Definition

A photon is a packet of light or electromagnetic radiation. picturegarden / Getty Images

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Updated July 24, 2017

Photon Definition: A photon is a discrete packet of energy associated with electromagnetic radiation (light). A photon has energy E which is proportional to the frequency ν of the radiation: E = hν, where h is Planck's constant.

Also Known As: quantum, quanta

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Science

Explanation of the Photoelectric Effect

The Photoelectric Effect

How to Solve an Energy From Wavelength Problem

What Spectroscopy Is and How It's Different From Spectrometry

What Exactly Is a Photon?

Here's an Example Problem to Help You Find Energy from Frequency

What Quantum Really Means in Science

Find Chemistry Definitions From A to Z

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What Is Electromagnetic Radiation?

What Is Blackbody Radiation?

What Is the De Broglie Hypothesis?

What the Compton Effect Is and Why It's Important in Physics

How Max Planck Discovered Quantum Physics

Radiation in Space: What It Can Teach us about the Universe

Heat Moves through the Cosmos via Heat Transfer