Planck constant

noun
\ˈpläŋk-\

Definition of Planck constant 

: the constant h in the Planck radiation law now found also in numerous formulas concerned with quantized energy and having a probable value of 6.626×10−27 erg second (g·cm2sec−1)

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First Known Use of Planck constant

1940, in the meaning defined above

History and Etymology for Planck constant

after Max K. E. L. Planck †1947 German physicist

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