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Physics · PYQ NEET UG 2019(2)
हिन्दीThe radius of the first permitted Bohr orbit, for the electron, in a hydrogen atom equals \( 0.51 \text{ \AA} \) and its ground state energy equals \( -13.6 \text{ eV} \). If the electron in the hydrogen atom is replaced by muon (\( \mu^- \)) [charge same as electron and mass \( 207 \text{ m}_e \)], the first Bohr radius and ground state energy will be,
Correct answer · Option 4
\( 2.56 \times 10^{-13} \text{ m}, -2.8 \text{ keV} \)
Explanation
Radius \( r \propto 1/m \), so \( r' = \frac{0.53 \times 10^{-10}}{207} \approx 2.56 \times 10^{-13} \text{ m} \). Energy \( E \propto m \), so \( E' = 207 \times (-13.6 \text{ eV}) \approx -2.82 \text{ keV} \).
