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प्रश्न
- Calculate the energy and momentum of a photon in a monochromatic beam of wavelength 331.5 nm.
- How fast should a hydrogen atom travel in order to have the same momentum as that of the photon in part (a)?
उत्तर
(a) Energy = E = `"hc"/λ`
or, E = `(6.6 xx 10^-34 xx 3 xx 10^8)/(331.5 xx 10^-9)`
∴ E = 6 × 10−19 J
Momentum = p = `"h"/λ`
Or, p = `(6.6 xx 10^-34)/(331.5 xx 10^-9)`
∴ p = 2 × 10−27 kg.m/s
(b) Momentum of Hydrogen atom = p = 2 × 10−27 kg.m/s
p = mv
Or, v = `"p"/"m"`
Or, v = `(2 xx 10^-27 "kg.m/s")/(1 "a.m.u")`
Or, v = `(2 xx 10^-27 "kg.m/s")/(1.66 xx 10^-27 "kg")`
∴ v = 1.2 m/s
संबंधित प्रश्न
Find the wave number of a photon having energy of 2.072 eV
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c) `E_"max" = hv + varphi_0`
d) `E_"max" = (hv)/lambda + varphi_0`
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