Answer:
True.
Explanation:
This phenomenon is called the photoelectric effect. Einstein was awarded with the Nobel Prize in 1921 "for his services to Theoretical Physics, and especially for his discovery of the law of the photoelectric effect."
The electrons are bound to the metal surfaces by the attractive force between the positive ions on the surface and the negative charge of the electrons. When the electrons absorb enough energy from the photons to overcome this attractive force, they can leave the surface.
