NEET-XII-Physics

42: Photoelectric Effect and Wave Particle Duality

with Solutions - page 3
Qstn# ii-13 Prvs-QstnNext-Qstn
  • #13
    A non-monochromatic light is used in an experiment on photoelectric effect. The stopping potential
    (a) is related to the mean wavelength
    (b) is related to the longest wavelength
    (c) is related to the shortest wavelength
    (d) is not related to the wavelength
    digAnsr:   c
    Ans : (c) is related to the shortest wavelength
    For photoelectric effect to be observed, wavelength of the incident light `` \left(\lambda \right)`` should be less than the threshold wavelength `` \left({\lambda }_{0}\right)`` of the metal.
    Einstein's photoelectric equation:
    `` e{V}_{0}=\frac{hc}{{\lambda }_{0}}-\phi ``
    Here, V0 = stopping potential
    `` {\lambda }_{0}`` = threshold wavelength
    h = Planck's constant
    `` \phi `` = work-function of metal
    It is clear from the above equation that stopping potential is related to the shortest wavelength (threshold wavelength).
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