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Physics · 2026 · 2 marks
CBSE 2026 · Region 3 · Set 1 · Q19
Explain the terms mass defect and binding energy. How are they related?
Explain the terms mass defect and binding energy. How are they related ?
Marking-scheme solution
The difference in mass of a nucleus and its constituents is called mass defect. If a certain number of neutrons and protons are brought together to form a nucleus of a certain mass and charge, the energy released is called binding energy.
\[\begin{aligned}
\mathrm{E}_{\mathrm{b}} & =\Delta \mathrm{Mc}^{2} \\
& =\left\lfloor\left[Z m_{p}+(A-Z) m_{n}\right]-\mathrm{M}\right\rfloor \mathrm{c}^{2}
\end{aligned}
\]
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