A light photon of wavelength `lambda_(0)` is absorbed by an atom of mass m at rest in ground state. The atom is free to move. The atom after absorbing the incident photon, emits another photon in direction opposite to that of the incident photon and returns back to its ground state. In the process the atom acquires a kinetic energy k. Find `lambda_(0)` in terms of k and m.
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The energy of a photon is given as, `Delta E`/atom `= 3.03 xx 10^(-19)J "atom"^(-1)` then, the wavelength `(lambda)` of the photon is
Correct Answer - C (c) According to formula =, `E=(hc)/(lambda)(v=(c)/(lambda))` Energy E=hv `3.03xx10^(-19)=(hc)/(lambda)` `lambda=(6.63xx10^(-34)xx3.0xx10^(8))/(3.03xx10^(-19))` `=6.56xx10^(-7) m` `=6.56xx10^(-7)xx10^(9)nm` =`6.56xx10^(2) nm` `=656 nm`
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A photon of energy `12.09 eV` is completely absorbed by a hydrogen atom initially in the ground state. The quantum number of excited state is
Correct Answer - C Energy difference in hydrogen atom `= 13.6 - (13.6)/(n^(2)) = 12.09 rArr n^(2) ~~ 9 rArr n = 3`
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Cut off potential for a metal in photoclectric effect for light of wavelength `lambda_(1), lambda_(2)` and `lambda_(3)` is found to be `V_(1),V_(2)` a
Correct Answer - C `eV_(1)=(hc)/lambda_(1) - phi, eV_(2)=(hc)/lambda_(2) - phi, eV_(3)=h_(0)/lambda_(3)-phi` if `2V_(2)=V_(1)+V_(3) implies 2/lambda_(2)=1/lambda_(1)+1/lambda_(2)` harmonic progression
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When radiations of wavelength `lambda_(1), lambda_(2) (= 0.6 lambda_(1)), lambda_(3) (= 4lambda_(2))` and `lambda_(4)` are incident on a metal plate,
Correct Answer - (a) `5 eV` , (b) `n = 6, Z = 3`
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A free hydrogen atom in its ground state is at rest. A neutron having kinetic energy `k_(0)` collides head one with the atom. Assume that mass of both
Correct Answer - (a) `20.4 eV` , (b) `8.72 eV` or `4.19 eV`
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A hydrogen atom in ground state is moving with a kinetic energy of 30 eV. It collides with a deuterium atom in ground state at rest. The hydrogen atom
Correct Answer - `20 eV, 13.2 eV`
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(a) The rest mass energy of an electron is `m_(0)c^(2)=0.51MeV`. Can a photon of this energy create an electron in free space? (A) A single photon of
Correct Answer - (a) No (b) `m_(0)=(h^(2)v^(2))/(2c^(2)[hv-2m_(0)c^(2)])`
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(a) If the wavelength of the light incident on a photoelectric cell be reduced from `lambda_(1)` to `lambda_(2) Å`, then what will be the change in th
Correct Answer - 2.3 eV, `1.44 xx 10^(-6)` Vm
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A hydrogen atom in ground state absorbs a photon of ultraviolet radiation of wavelength `50 nm` Assuming that the entire photon energy is taken up by
Correct Answer - `[11.2eV]`
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The minimum kinetic energy of a ground state hydrogen atom required to have head-on collision with another ground state hydrogen atom but at rest to p
Correct Answer - 20.4 eV
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