Question
If the potential difference used to accelerate electrons is tripled, by what factor does de Broglie wavelength of electrons beam change?
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Answer
de Broglie wavelength of electrons accelerated through a potential difference of V volts is $\lambda=\frac{\text{h}}{\sqrt{2\text{meV}}}$
When accelerating voltage V is tripled, the de Broglie wavelength becomes $\frac{1}{\sqrt{3}}$ times.
When accelerating voltage V is tripled, the de Broglie wavelength becomes $\frac{1}{\sqrt{3}}$ times.
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