Medium MCQ +4 / -1 PYQ · JEE Mains 2021

The speed of electrons in a scanning electron microscope is 1 $\times$ 107 ms-1. If the protons having the same speed are used instead of electrons, then the resolving power of scanning proton microscope will be changed by a factor of :

  1. A ${1 \over {1837}}$
  2. B 1837 Correct answer
  3. C ${\sqrt {1837} }$
  4. D ${1 \over {\sqrt {1837} }}$

Solution

Resolving power (RP) $\propto$ ${1 \over \lambda }$<br><br>We know, de-Broglie wavelength<br><br>$\lambda = {h \over {mv}}$<br><br>$\therefore$ RP $\propto$ ${mv \over {h}}$<br><br>$\therefore$ ${{R{P_e}} \over {R{P_p}}} = {{{m_e}} \over {{m_p}}} = 1837$

About this question

Subject: Physics · Chapter: Dual Nature of Matter and Radiation · Topic: Photoelectric Effect

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