Cellula fotoelettrica di quarzo BKE su piede

Descrizione e caratteristiche fisiche

For demonstrating the photoelectric effect with visible light, for investigating the frequency dependency of the photoelectric current and for determination of Planck's constant based on the counter-field method. Vacuum photocell with large-surface alkaline cathode and annular platinum electrode which can be heated in order to clean off impurities from the cathode coating.

The photo cell is used to demonstrate the photoelectric effect. When the photocathode is irradiated with light, electrons are liberated from the photocathode and can be detected at the anode ring as a photoelectric current in a suitable circuit. This device can be used to show that the energy of the light is proportional to the frequency of the radiation and independent of the intensity of the radiation. When the photocathode is irradiated with monochromatic light, it is possible to determine Planck’s constant. In addition to confirming Planck’s calculations for the radiation of a black body, Einstein’s interpretation of these experiments confirmed the quantum nature of light.