Question:
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:
Correct Option: , 4
Solution:
$\mathrm{q} \Delta \mathrm{V}=\frac{1}{2} \mathrm{mV}^{2} \Rightarrow \mathrm{v}=\sqrt{\frac{2 \mathrm{q} \Delta \mathrm{V}}{\mathrm{m}}}$
$\therefore \frac{V_{1}}{V_{2}}=\sqrt{\frac{e}{m} \frac{4 m}{e}}=2$