NEET Physics Photo Electric Effect, X- Rays & Matter Waves NEET PYQ-Photo Electric Effect,X-Rays

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:              [NEET 2020]

A) \[{{10}^{2}}V\]

B)      \[{{10}^{3}}V\]

C) \[{{10}^{4}}V\]

D)      \[10\,V\]

Correct Answer: C

Solution :

[c] \[\lambda =\frac{12.27}{\sqrt{V}}\overset{o}{\mathop{A}}\,\]

\[\sqrt{V}=\frac{12.27\times {{10}^{-10}}}{1.227\times {{10}^{-11}}}={{10}^{2}}\]

\[\therefore V={{10}^{4}}\,\text{volts}\]