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NEETPhysicsDual Nature of Matter

Consider a 20 W bulb emitting light of wavelength 5000 Å and shining on a metal surface kept at a distance of 2 m. Assume that the metal surface has a work function of 2 eV, and that each atom on the metal surface can be treated as a circular disk of radius 1.5 Å. Estimate the number of photons emitted by the bulb per second. [Assume no other losses]

Options

  1. A1×10 18 /s
  2. B2×10 19/ s
  3. C5×10 19 /s
  4. D1×10 20 /s

Correct answer

C. 5×10 19 /s

Step-by-step solution

Correct Option is : (C) 5×10 19 /s

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