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NEETPhysicsDual Nature of Matter

"A 20 W bulb emits light of wavelength 5000 Å shining on a metal surface at a distance of 2 m. Assuming the metal surface has a work function of 2 eV, and each atom on the surface can be treated as a circular disk with a radius of 1.5 Å. What is the time required for the atom to receive energy equal to the work function of 2 eV?"

Options

  1. A30 s
  2. B25 s
  3. C20 s
  4. D28.4 s

Correct answer

D. 28.4 s

Step-by-step solution

Correct Option is : (D) 28.4 s

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