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NEET2011PhysicsDual Nature of MatterActual

The threshold frequency for a photo-sensitive metal is 3.3 10¹⁴ ~Hz . If light of frequency 8.2 10¹⁴ ~Hz is incident on this metal, the cut-off voltage for the photo-electric emission is nearly

Options

  1. A2 ~V
  2. B3 ~V
  3. C5 ~V
  4. D1 ~V

Correct answer

A. 2 ~V

Step-by-step solution

aligned V₀ & = E-V e & = h (v-v₀ ) e & = 6.62 10⁻³⁴ (8.2 10¹⁴-3.3 10¹⁴ ) 1.6 10⁻¹⁹ & = 6.62 10⁻³⁴ 1.6 4.9 10³³ & = 6.62 4.9 10⁻¹ 1.6 aligned V₀=2 volt

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