2.2.1 The Photoelectric Effect

Question 1

Define photoelectric effect?

Answer 1

If a radiation of a high enough frequency (usually in the ultraviolet range) is shone on the surface of a metal, it will instantly emit electrons.

Question 2

Why does photoelectric effect occur?

Answer 2

Atoms bonded in metals have free electrons that are able to move through the metal. these electrons near the surface are able to absorb energy from radiation and vibrate. If they absorbed enough energy. the bonds break and the electron is released as a photoelectron in the photoelectric effect.

Question 3

What 4 conclusions can be made form the photoelectric effect experiment?

Answer 3

1) No photoelectrons are emitted if radiation has frequency below a certain value (threshold frequency).
2) Photoelectrons are emitted with a variety of kinetic energies from zero to a maximum value. Maximum of the KE increases with radiation.
3) The intensity of radiation