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The vapours of Hg absord some electron a...

The vapours of Hg absord some electron accelerated by a potiential diff. of 4.5 volt as a result of which light is emitted . If the full energy of single incident `e^(-)` is supposed to be converted into light emitted by single Hg atom , find the wave no. of the light

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The correct Answer is:
`3.63xx10^(6)m^(-1)`

`4.5 eV = (1240)/(lambda(nm))" "(1)/(lambda)=(4.5)/(1240)`
`(1)/(lambda)=0.0036nm^(-1)" "1nmrarr10^(-9)m^(-1)`
`0.0036nm^(-1)" "1nmrarr10^(-9)m^(-1)`
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ALLEN-ATOMIC STRUCTURE-Exercise - 04[A]
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  2. The energy of an excited H-atom is -3.4eV. Calculate angular momentum ...

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  3. The vapours of Hg absord some electron accelerated by a potiential di...

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  4. The hydrogen atom in the ground state is excited by means of monochrom...

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  5. If the average life time of an excited state of hydrogen is of the ord...

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  6. Calculate the velocity of an electron in the first Bohr orbit of a ...

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  7. A single electron orbits around a stationary nucleus of charge + Ze wh...

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  8. Stationary He^(o+) ion emits a photon corresponding to the first line ...

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  9. To what series does the spectral lines of atomic hydrogen belong if ...

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  10. A particle of charge equal to that of an electron and mass 208 times t...

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  12. Calculate the threshold frequency of metal if the binding energy is 18...

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  13. Calculate the binding energy per mole when threshold wavelength of pho...

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  14. When a certain metal was irradiated with light of frequency 3.2 xx ...

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  15. U.V. light of wavelength 800A^(@)&700A^(@) falls on hydrogen atoms in ...

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  16. A potential diffrence , the 20kv is applied across an X- ray s tube ....

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  17. The K.E. of an electron emitted from tungsten surface is 3.06 eV. What...

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  18. What is de-Broglie wavelength of a He-atom in a container at room temp...

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