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Dual Nature of Radiation and Matter — Physics STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsDual Nature of Radiation and Matter1 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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