Alexander Fufaev
My name is Alexander FufaeV and here I write about:

What is the Planck's Constant?

The Planck's constant \( h \) is a physical constant that appears in equations whenever the equation describes quantum phenomena. For example, it appears in the light quantum hypothesis:

In this equation Planck's constant connects the energy \( W_{\text p} \) of a photon (light particle) with the light frequency \( f \). From this equation you can also read the unit of the Planck's constant, if you rearrange the equation for \(h\): Js (Joule seconds).

You can measure the value of the Planck's constant, for example, using the photoelectric effect. It has the value:

In the photoelectric effect there is a linear relation between kinetic energy of the released electrons \( W_{\text{kin}} \) and photon frequency \( f \). The Planck's constant \( h \) is the slope of the straight line.