Physics-
General
Easy
Question
In an electron gun the control grid is given a negative potential relative to cathode in order to
- Decelerate electrons
- Repel electrons and thus to control the number of electrons passing through it
- To select electrons of same velocity and to converge them along the axis
- To decrease the kinetic energy of electrons
The correct answer is: Repel electrons and thus to control the number of electrons passing through it
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