It has been determined experimentally that when light falls on a metal surface, the surface emits electrons. For example, you can start a current in a circuit just by shining a light on a metal plate. a. What is your explanation? b. Mention some other methods in which electron emission is possible. c. Are stopping potential and cut off potential the same?

It has been determined experimentally that when light falls on a metal

1.	It has been determined experimentally that when light falls on a metal surface, the surface emits electrons. For example, you can start a current in a circuit just by shining a light on a metal plate. a. What is your explanation? b. Mention some other methods in which electron emission is possible. c. Are stopping potential and cut off potential the same?
Answer» Solution :a. The electrons in the metal surface absorb photon ENERGY and are emitted. b. Thermionic EMISSION, PHOTOELECTRIC effect, field emission, secondary emission. c. Yes

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