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What Is the Planck Constant?

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, which can be downloaded as a poster. We also have versions of this infographic to share on your social media.

Infographic reads "What is the Planck Constant?" with an explanation involving coffee and sugar.
Credit: B. Hayes/NIST


Created January 13, 2023