Hydrogen ion and singly ionized helium atom are accelerated, from rest, through the same potential difference. The ratio of final speeds of hydrogen and helium ions is close to :
Solution
We know, kinetic energy K = qV
<br><br>also $K = {{{P^2}} \over {2m}}$<br><br>$\therefore$ $qV = {{{P^2}} \over {2m}} = {{{m^2}{v^2}} \over {2m}}$<br><br>$V = \sqrt {{{2qv} \over m}}$<br><br>$V \propto \sqrt {{q \over m}}$<br><br>$${{{V_H}} \over {{V_{He}}}} = {{\sqrt {{e \over m}} } \over {\sqrt {{e \over {4m}}} }} = {2 \over 1}$$
About this question
Subject: Physics · Chapter: Atoms and Nuclei · Topic: Bohr's Model of Hydrogen Atom
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