11. |
What is the angular momentum of an electron of Li-atom in n = 5 orbit.
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Answer:
Option (a) |
12. |
The wavelengh of the first line of Lyman series is λ. The wavelengh of the first line in Balmer series is _____ .
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Answer:
Option (a) |
13. |
The difference of wave numbers of lines with maximum and minimum wavelengths in Balmer series of hydrogen atom is _____ m-1. (R = 1.097 × 107 m-1)
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Answer:
Option (a) |
14. |
In hydrogen atom, an electron makes transition from n = 3 to n = 1 state in time interval of 1.2 × 10-8 s calculate average toque (in Nm) acting on the electron during this transition.
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Answer:
Option (c) |
15. |
In which of the following system will the radius of the 2nd orbit be minimum ?
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Answer:
Option (b) |
16. |
The ionization potentials of hydrogenic ions A and B are VA and VB , respectively. Now if VB > VA then _____
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Answer:
Option (a) |
17. |
The operating voltage in Coolidge tube is 105 V. The speed of X-rays produced is ____ms-1.
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Answer:
Option (d) |
18. |
The wavelength of Kα spectral line is λ for an element of atomic number 43. The wavelength of Kα line for an element with atomic number 29 is ____ λ.
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Answer:
Option (c) |
19. |
If f1, f2 and f3 are the frequencies corresponding to Kα, Kβ and Lα X-rays for the given target. Then ____
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Answer:
Option (c) |
20. |
The spectral lines of pfund series lies in the _____ region.
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Answer:
Option (b) |