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Question
Explain the concept of the photoelectric effect.
Solution
- The phenomenon of emission of electrons from a metal surface, when radiation of appropriate frequency is incident on it, is known as the photoelectric effect.
- The emitted electrons are called photoelectrons and the resulting current in the circuit due to them is called photoelectric current.
- When ultraviolet radiations fall on the emitter plate, electrons are ejected from it.
- They are attracted towards the positive collector plate by the electric field. Thus, light falling on the surface of the emitter causes a current in the external circuit.
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