InterviewSolution
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InterviewSolution
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To produce characteristic `X` - rays using a Tungsten target in an x - ray generator , the accelerating should be greater then ……. Volts and the energy of the characteristion is …… eV . (The binding energy of the intermost electron in Tungsten is - 40keV). |
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Answer» Correct Answer - C For minimum accelerating voltage , the electron should jump from `n = 2`to`n = 1leval` for characterintic X - rays `(1)/(lambda) = R_(a)(L-1)^(2) [1 - (1)/(n^(2))] = (E)/ (hc) ( E_(1))/(hc) = R_(a) (Z - 1)^(2)[1 -(1)/(2^(2)) ] ` …..(i) The binding energy of innermost eletron ` = 40 keV` ` `:.` lonisation potential of tungsten ` = 40 kV = 40 xx 10^(2) V` `rArr (E_(2))/(hc) = R_(a) (Z - 1)^(2)[1 -(1)/(2^(2)) ] ` ....(ii) ` (E_(1))/(E_(2)) = [[1 - (1)/(2^(2))]]/([1 - (1)/(oo^(2)]]` `rArr E_(1) = (3)/(4) E_(2) = (3)/(4) xx 40000 eV = 30000 eV` `:. ` Minimum accelerating vollage `V_(min) = (E_(1))/(e) = 30000 V ` |
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