The mass of proton, neutron and helium nucleus are respectively $1.0073~u,1.0087~u$ and $4.0015~u$. The binding energy of helium nucleus is :
Solution
Mass defect $=2($ Mass of $p+$ mass of $n)-$ mass of $\mathrm{He}$ nucleus
<br/><br/>$$
\begin{aligned}
& \Delta m=0.0305 u \\\\
& \text { B.E }=931.5 \times \Delta m=931.5 \times 0.0305 \\\\
& =28.4 \mathrm{MeV}
\end{aligned}
$$
About this question
Subject: Physics · Chapter: Atoms and Nuclei · Topic: Bohr's Model of Hydrogen Atom
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