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Electron, Photon, Photo-electric Effect and X-Rays — JEE physics STD 12 Science — Question

CBSE BoardEnglish MediumSTD 12 ScienceJEE physicsElectron, Photon, Photo-electric Effect and X-Rays1 Mark
MCQ
In an electron gun the control grid is given a negative potential relative to cathode in order to
  • A
    Decelerate electrons
  • ✓
    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

Correct option: B.
Repel electrons and thus to control the number of electrons passing through it

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