Physics · 2026
JEE Main · 21 January 2026, Shift 1 · Q41
If an alpha particle with energy 7.7 MeV is bombarded on a thin gold foil, the closest distance from nucleus it can reach is ____ m. (Atomic number…
If an alpha particle with energy $\displaystyle 7.7$ MeV is bombarded on a thin gold foil, the closest distance from nucleus it can reach is $\displaystyle \_\_\_\_$ m. (Atomic number of gold $\displaystyle =79$ and $\displaystyle \frac{1}{4 \pi \epsilon_{\mathrm{o}}}=9 \times 10^9$ in SI units)
Official answer
From NTA’s final answer key for this paper.
(1)
$\displaystyle 2.95 \times 10^{-14}$
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JEE Main 2026 Physics question, with the answer from NTA’s final answer key. Where our answers come from.