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प्रश्न
State how will you use this graph to detennine the value of Planck's constant.
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उत्तर
From the graph the slope , tan θ = `(V_s)/f`
⇒ tan `theta =h/e [∵V_s =h/ef]`
∴ h = Planck's constant = e tan θ
Thus, knowing the slope we can get the value of 'h' - Planck's constant
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संबंधित प्रश्न
The photoelectric work function for a metal surface is 2.3 eV. If the light of wavelength 6800A is incident on the surface of metal, find threshold frequency and incident frequency. Will there be an emission of photoelectrons or not?
[Velocity of light c = 3 x 108 m/s,
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(i) In which case is the stopping potential more and why?
(ii) Does the slope of the graph depend on the nature of the material used? Explain.
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The graph shows the variation of stopping potential with frequency of incident radiation for two photosensitive metals A and B. Which one of the two has higher value of work-function? Justify your answer.
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Velocity of light = 3 x 108 m/s; 1 eV = 1.6 x 10–19 J]
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