请输入您要查询的字词:

 

单词 Planck constant
释义
Planck constant

Physics
  • Symbol h. The fundamental constant equal to the ratio of the energy E of a quantum of energy to its frequency ν‎: E=hν‎. It has the value 6.626 176×10−34 J s. It is named after Max Planck. In quantum-mechanical calculations (especially particle physics) the rationalized Planck constant ћ=h/2π‎=1.054 589×10−34 J s is frequently used. It is also known as the Dirac constant.


Astronomy
  • A constant that relates the energy of a photon to its frequency. It is measured in joule-seconds (J s) and has the value 6.626 070 040 × 10–34 J s. It is named after the German physicist Max Karl Ernst Ludwig Planck (1858–1947).


Chemistry
  • The fundamental constant equal to the ratio of the energy of a quantum of energy to its frequency. It is defined as having a value of exactly 6.626 07015 × 10−34 Js. Because the Planck constant has been measured very accurately, it is now (since May 2019) used in the definition of the kilogram. In quantum-mechanical calculations the rationalized Planck constant (or Dirac constant) ħ = h/2π‎ = 1.054 57180 × 10−34 Js is frequently used.


随便看

 

科学参考收录了60776条科技类词条,基本涵盖了常见科技类参考文献及英语词汇的翻译,是科学学习和研究的有利工具。

 

Copyright © 2000-2023 Sciref.net All Rights Reserved
京ICP备2021023879号 更新时间:2024/12/25 16:21:49