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

Bihar BoardEnglish MediumSTD 12 SciencePhysicsDual Nature of Radiation and Matter1 Mark
MCQ
Threshold frequency is the frequency :
  • A
    Below which, the value of photoelectric current remains constant.
  • B
    Below which, the photoelectric current increases with the potential difference.
  • C
    At frequencies higher than this the photo-electric current becomes saturated.
  • ✓
    Photo-electrons are not emitted at frequencies lower than this.
✓

Answer

Correct option: D.
Photo-electrons are not emitted at frequencies lower than this.
(D) - Photo-electrons are not emitted at frequencies lower than this.

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