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NEET2019PhysicsDual Nature of MatterActual

The maximum velocities of the photoelectrons ejected are v and 2 v for the incident light of wavelength 400 ~nm and 250 ~nm on a metal surface respectively. The work function of the metal in terms of Planck's constant h and velocity of light c is

Options

  1. Ah c 10^6 ~J
  2. B2 h c 10^6 ~J
  3. C1.5 h c 10^6 ~J
  4. D2.5 h c 10^6 ~J

Correct answer

B. 2 h c 10^6 ~J

Step-by-step solution

As per question Solving eqns. (i) and (ii), we get aligned & h c 250 ~nm - ₀= 4 h c 400 ~nm -4 ₀ & or ₀= h c 500 10⁻⁹ ~J = 10^9 h c 500 ~J = 1000 h c 500 10^6 ~J aligned =2 h c 10^6 ~J

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