MCQ
$Q$ value for neutron decay is:
- ✓$0.782\ MeV$
- B$0.782\ eV$
- C$78.2\ MeV$
- D$0$
✓
Answer
Correct option: A.
$0.782\ MeV$
For neutron decay, some mass disappears as neutrons convert to a proton, electron and antineutrino.
$Q=\left(m_n-m_p-m{_v}^--m_e\right) c^2=0.782 \mathrm{MeV}$
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