A photographic film is coated with a silver bromide layer. When light falls on this film, silver bromide molecules dissociate and the film records the light there. A minimum of 0.6 eV is needed to dissociate a silver bromide molecule. Find the maximum wavelength of light that can be recorded by the film.
Given, work function Ф=0.6eV
We know that Ф=hc/λ
Where h is the Planck’s constant
C is the speed of the light
λ is the wavelength of the light.
∴ for λ to be maximum Ф should be minimum
⇒ 
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