The energy of light

It is enough to extend your hand to the spring Sun, to understand that the light carries the energy. But one hundred years ago or so (exactly on Thursday, Dec. 14th, 1900) the German physicist, Max Planck made a revolutionary statement:

       

The light carries the energy in little portions, called quanta. And the energy of these elementary quanta does not depend on the intensity of the light, but on the colour. Say, the blue quanta bring more energy that the red ones.

  

 

The interactive lesson by prof. Grzegorz Karwasz is intended to show it. As long as the various colours of girls’ hair are illuminated by the red LED, nobody is able to guess a single shade. With the green illumination already the orange and yellow colours become visible, and with the blue LED illumination even the cyan colour.

The whole lesson is much of the surprise and much of the fun!

Text: Grzegorz Karwasz

Photo: Marta Nowicka

Lay-out: Klaudia Gackowska