Q 12-11-014NEETNEET 2020Top questionEasy
An electron is accelerated from rest through a potential difference of V volt. If the de Broglie wavelength of the electron is $1.227 \times 10^{-2}$ nm, the potential difference is :
Answer: (D) $10^4$ V
For an electron accelerated through $V$ volts: $\lambda = \dfrac{1.227}{\sqrt{V}}$ nm.
$$\sqrt{V} = \frac{1.227}{1.227 \times 10^{-2}} = 100 \;\Rightarrow\; V = 10^4\ \text{V}$$
Solution by Sreeraj P, M.Sc Physics