Easy MCQ +4 / -1 PYQ · JEE Mains 2021

The de-Broglie wavelength associated with an electron and a proton were calculated by accelerating them through same potential of 100 V. What should nearly be the ratio of their wavelengths? (mp = 1.00727u me = 0.00055u)

  1. A 41.4 : 1
  2. B (1860)<sup>2</sup> : 1
  3. C 1860 : 1
  4. D 43 : 1 Correct answer

Solution

${\lambda _e} = {{12.27} \over {\sqrt V }}\mathop A\limits^o$<br><br>${\lambda _p} = {{0.286} \over {\sqrt V }}\mathop A\limits^o$<br><br>${{{\lambda _e}} \over {{\lambda _p}}} = {{12.27} \over {0.286}} = 43$

About this question

Subject: Physics · Chapter: Dual Nature of Matter and Radiation · Topic: de Broglie Hypothesis

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