Q 12-11-116JEE MainJEE Main 2022 (28 Jul, Shift 1)Easy
The equation $\lambda = \dfrac{1.227}{x}$ nm can be used to find the de-Broglie wavelength of an electron. In this equation $x$ stands for :
Where, $m$ = mass of electron, $P$ = momentum of electron, $K$ = Kinetic energy of electron, $V$ = Accelerating potential in volts for electron
Answer: (D) $\sqrt V$
For an electron accelerated through $V$ volts:
$$\lambda = \frac{h}{\sqrt{2meV}} = \frac{1.227}{\sqrt V}\ \text{nm}$$
So $x = \sqrt V$.
Solution by Sreeraj P, M.Sc Physics