The constant factor which relates the energy of a photon to its frequency. Symbol, h. According to the 2006 CODATA recommended values, it is 6.626 068 96 × 10−34 joule-seconds, with a standard uncertainty of 0.000 000 33 × 10−34.
It is named for the German physicist Max Planck.
It is often encountered as the reduced Planck constant, symbol ħ (pronounced "h bar"), which is h divided by 2 pi, or 1.054 571 628 x 10-34 J s.
| home | | | nature index | | | search | | | your comments  | | | about | | | help | | |
Copyright © 2000 Sizes, Inc. All rights reserved.
Last revised: 19 January 2009.