A beam of monochromatic light is used to excite the electron in Li+ + from the first orbit to the third orbit. The wavelength of monochromatic light is found to be x $\times$ 10$-$10 m. The value of x is ___________.
[Given hc = 1242 eV nm]
Answer (integer)
114
Solution
<p>E(in eV) = 13.6 $\times$ 9$\left( {1 - {1 \over 9}} \right)$</p>
<p>= 13.6 $\times$ 8 eV</p>
<p>$\Rightarrow$ $\lambda = {{12420} \over {13.6 \times 8}}\mathop A\limits^o$</p>
<p>= 114.15 $\mathop A\limits^o$</p>
About this question
Subject: Physics · Chapter: Atoms and Nuclei · Topic: Bohr's Model of Hydrogen Atom
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