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Atoms — Physics STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 SciencePhysicsAtoms1 Mark
MCQ
In an electron gun the control grid is given a negative potential relative to cathode in order to:
  • A
    Decelerate electrons
  • B
    Repel electrons and thus to control the number of electrons passing through it
  • C
    To select electrons of same velocity and to converge them along the axis
  • D
    To decrease the kinetic energy of electrons
✓

Answer

  1. Repel electrons and thus to control the number of electrons passing through it

Explanation:

You must know the working of an electron gun.

In an electron gun the control grid is given a negative potential relative to cathode in order to repel electrons and thus to control the number of electrons passing through it.

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