Question

An electron and a photon have equal energy $E_k$. Then, the ratio of wavelengths of photon and electron is $\left(\frac{{\lambda }_{photon}}{{\lambda }_{electron}}\right)$

• A. $\frac{\sqrt{E_K}}{2}$
• B. $\frac{1}{\sqrt{2E_K}}$
• C. $\frac{1}{\sqrt{E_K}}$
• D. $\frac{\sqrt{3E_K}}{2}$

Answer 1

Answer: (C)

$\frac{1}{\sqrt{E_K}}$

${\lambda }_{photon}=\frac{hc}{E_k}$

${\lambda }_{electron}=\frac{h}{\sqrt{2m{E}_k}}$

$\frac{{\lambda }_{photon}}{{\lambda }_{electron}}=\frac{1}{\sqrt{E_k}}$