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Question
A non-monochromatic light is used in an experiment on photoelectric effect. The stopping potential
Options
is related to the mean wavelength
is related to the longest wavelength
is related to the shortest wavelength
is not related to the wavelength
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Solution
is related to the shortest wavelength
For photoelectric effect to be observed, wavelength of the incident light `(λ)` should be less than the threshold wavelength `(λ_0)` of the metal .
Einstein's photoelectric equation :
`eV_0 = (hc)/(λ_0) - varphi`
Here, V0 = stopping potential
`λ_0` = threshold wavelength
h = Planck's constant
`varphi` = 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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