Question

The de Broglie wavelength of an electron is $1.224nm$ . The energy of electron is $eV$ is

• A. 1 eV
• B. 10 eV
• C. 100 eV
• D. 1015 eV

Answer 1

The correct option is D 1015 eV

Energy, $E=\frac{hc}{\lambda }$

$\Rightarrow E=\frac{6.626\times {10}^{-34}\times 3\times {10}^8}{1.224\times {10}^{-9}}$Joule

$\Rightarrow E=16.24\times {10}^{-17}J$

$\Rightarrow E=\frac{16.24\times {10}^{-17}}{1.6\times {10}^{-19}}eV$

$\Rightarrow E=1015eV$

Hence, the correct option is D.