Question
The wavelength associated with an electron accelerated through a potential difference of $100 V$ is nearly .............. $\mathop {\rm{A}}\limits^o $
✓
Answer
(c) $\lambda = \frac{h}{{\sqrt {2mQV} }} = \frac{{6.6 \times {{10}^{ - 34}}}}{{\sqrt {2 \times 9.1 \times {{10}^{ - 31}} \times 1.6 \times {{10}^{ - 19}} \times 100} }}$
$ = 1.23\,{Å}$
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