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NEETPhysicsDual Nature of Matter

A monochromatic light source of wavelength and intensity I illuminates a photosensitive metal surface, producing a non-zero photoelectric current. When this source is replaced by another monochromatic light source of wavelength ' and intensity 4I , the photoelectric current drops to zero. Which of the following inequalities correctly represents the work function of the metal?

Options

  1. A> hc and > hc '
  2. Bhc < hc '
  3. Chc ' < hc
  4. D4hc '

Correct answer

C. hc ' < hc

Step-by-step solution

For the first light source of wavelength , a non-zero photoelectric current is observed. This means photoelectric emission takes place, so the energy of the incident photons must be strictly greater than the work function of the metal: hc > For the second light source of wavelength ' , the photoelectric current is zero. This implies that no photoelectric emission occurs, meaning the energy of the incident photons is less than or equal to the work function of the metal: hc ' The intensity of the light only affects t

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