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Physics

The Planck Constant

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Quantum mechanics, the science of atoms, has enabled the invention of smartphones, solar panels and GPS navigation. In quantum mechanics, energy is exchanged and absorbed in specific amounts, known as quanta. The Planck constant is a number that defines the amount of energy in those quanta and expresses how small things can be. Learn more about the Planck constant in this infographic. And if you’d like to share more social-media-friendly versions of this infographic on your social media, check out these.

Infographic titled What is the Planck Constant? explains the constant and its importance.
Credit: B. Hayes/NIST

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Illustration says "What is the Planck Constant?" with explanation.
Credit: B. Hayes/NIST
Illustration says "Why is the Planck constant important?" with examples of computer chips, lasers, etc.
Credit: B. Hayes/NIST
Illustration says "So what is the value of the Planck constant?" with explanation.
Credit: B. Hayes/NIST
Illustration explains the Planck Constant using the example of coffee and sugar.
Credit: B. Hayes/NIST

To learn more about the Planck constant and other important constants in measurement science, visit our SI redefinition page. 

Physics and Quantum information science
Created April 7, 2022, Updated April 11, 2022