Given the masses of various atomic particles... | Nuclear Physics

JEE MAIN 2020

09-06-2020 S2

Question

Given the masses of various atomic particles $\mathrm{m}_{\mathrm{p}}= 1.0072 \mathrm{u}, \mathrm{m}_{\mathrm{n}}=1.0087 \mathrm{u}, \mathrm{m}_{\mathrm{e}}=0.000548 \mathrm{u}$, $\mathrm{m}_{\mathrm{v}}^{-}=0, \quad \mathrm{~m}_{\mathrm{d}}=2.0141 \mathrm{u}$, where $\mathrm{p} \equiv$ proton, $\mathrm{n} \equiv$ neutron, $\mathrm{e} \equiv$ electron, $\overline{\mathrm{v}} \equiv$ antineutrino and $\mathrm{d} \equiv$ deuteron. Which of the following process is allowed by momentum and energy conservation?

Select the correct option:

$n+n \rightarrow$ deuterium atom (electron bound to the nucleus)

$n+p \rightarrow d+\gamma$

$\mathrm{p} \rightarrow \mathrm{n}+\mathrm{e}^{+}+\overline{\mathrm{v}}$

$\mathrm{e}^{+}+\mathrm{e}^{-} \rightarrow \gamma$

✓ Correct! Well done.

✗ Incorrect. Try again or view the solution.

Solution

$\Delta \mathrm{m}$ should be positive $$ \left(m_p+m_n\right)>m_d $$ $\Rightarrow \quad$ only (2) is possible

Question Tags

JEE Main

Physics