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NEET2007PhysicsDual Nature of MatterActual

Monochromatic light of frequency 6.0 10¹⁴ ~Hz is produced by a laser. The power emitted is 2 10⁻³ ~W . The number of photons emitted, on the average, by the source per second is:

Options

  1. A5 10¹⁶
  2. B5 10¹⁷
  3. C5 10¹⁴
  4. D5 10¹⁵

Correct answer

D. 5 10¹⁵

Step-by-step solution

= p m v = 2 10⁻³ 6.62 10⁻³⁴ 6 10¹⁴ =5 10¹⁵

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