Question

Which of the following particle has the shortest de-Broglie wavelength ?

• A. Proton
• B. Electron
• C. $\alpha$ - particle
• D. X- rays

Answer 1

Answer: (C)

By using de-Broglie wavelength,
$\lambda =\frac{h}{p}=\frac{h}{mv}$
$\lambda \propto \frac{1}{m}$
Since, $\alpha$-particle is the heavier most.
$\therefore \lambda$ of $\alpha$-particle will be least.