InterviewSolution
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InterviewSolution
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An electron is continuonsly accelerated in vacume tube by appliying potential difference if its de Brogle wavelength is decresed by `1%` the change in the kinetic energy of the electron is nearlyA. Decreased by `1%`B. Increased by `2%`C. Increased by `1%`D. Decreased by `2%` |
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Answer» Correct Answer - B `(hc)/(lambda)=E_(1)-E_(2)=KE_(2)-KE_(1)` `:. Lambda=h/(mV) (mV)^(2)=(h/lambda)^(2), 1/2 mV^(2)=1/(2m)h^(2)/lambda^(2)` `:. (hc)/lambda=h^(2)/(2m lambda_(2)^(2))-h^(2)/(2mlambda_(1)^(2)) :. Lambda=(2mc)/(h){(lambda_(1)^(2)lambda_(2)^(2))/(lambda_(1)^(2)-lambda_(2)^(2))}` |
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