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प्रश्न
Find energy of each of the photons which have the wavelength of 0.50 Å.
उत्तर
Energy (E) of a photon having wavelength (λ) is given by the expression `"E" ="hc"/lambda`
h = Planck’s constant = 6.626 × 10–34 Js
c = velocity of light in vacuum = 3 × 108 m/s
Substituting the values in the given expression of E:
`E = ((6.626 xx 10^(-34))(3 xx 10^8))/(0.50 xx 10^(-10)) = 3.976 xx 10^(-15) J`
`therefore "E" = 3.98 xx 10^(-15) " J"`
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