Which radiations will be most effective for the emission of electrons from a metallic surface?
Show Hint
- Microwaves
- X-rays
- Ultraviolet
- Infrared
The Correct Option is C
Solution and Explanation
The photoelectric effect occurs when light of a sufficiently high frequency strikes a metal surface and ejects electrons.
The frequency of the light must be above a certain threshold frequency to overcome the work function of the metal.
Step 2: Identify the most effective radiation.
Ultraviolet radiation has higher energy than visible light, and its frequency is above the threshold for most metals, making it the most effective for the emission of electrons.
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