A) eV to 0.4 eV
B) 0.5 eV to 0.8 eV
C) 0.9 eV to 1.6 eV
D) 1.7 eV to 3.0 eV
Correct Answer: D
Solution :
Energy band gap range is given by, \[{{E}_{g}}=\frac{hc}{\lambda }\] For visible region \[\lambda =\left( 4\times {{10}^{-7}}\tilde{\ }7\times {{10}^{-7}} \right)m\] \[{{E}_{g}}=\frac{6.6\times {{10}^{-34}}\times 3\times {{10}^{8}}}{7\times {{10}^{-7}}}\] \[=\frac{19.8\times {{10}^{-26}}}{7\times {{10}^{-7}}}\] \[=\frac{2.8\times {{10}^{-19}}}{1.6\times {{10}^{-19}}}\] \[{{E}_{g}}=1.75eV\]You need to login to perform this action.
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