Browse Questions

Assuming the velocity to be same,which sub-atomic particle possesses smallest de-Brogile wavelength

$\begin{array}{1 1}(a)\;\text{An electron}\\(b)\;\text{A proton}\\(c)\;\text{An }\alpha-\text{particle}\\(d)\;\text{All have same wavelength}\end{array}$

Toolbox:
• Ratio of the mass of proton and $\alpha$ particle is 1 : 4.
• Mass of electron compared to proton and alpha particle is negligible.
• De-Broglie wavelength $\lambda=\large\frac{h}{mu}$
Since, de-Broglie wavelength $\lambda=\large\frac{h}{mu}$
$\therefore \lambda \propto \frac{1}{m}$
Hence, heavier the particle, lesser the wavelength.
$\therefore$ The particle posessing smallest de-Broglie wavelength is $\alpha$-particle
Hence (c) is the correct answer.
edited Mar 19, 2014