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NEET2009PhysicsDual Nature of MatterActual

Monochromatic light of wavelength 667 ~nm is produced by a helium neon laser. The power emitted is 9 ~mW . The number of photons arriving per second on the average at a target irradiated by this beam is :

Options

  1. A3 10¹⁹
  2. B9 10¹⁷
  3. C3 10¹⁶
  4. D9 10¹⁵

Correct answer

C. 3 10¹⁶

Step-by-step solution

array r No. of photons = E ( hc / ) = 9 10⁻³ 6.67 10⁻⁷ 6.6 10⁻³⁴ 3 10^8 =3 10¹⁶ array

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