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Physics · PYQ NEET UG 2025
हिन्दीA model for quantized motion of an electron in a uniform magnetic field \( B \) states that the flux passing through the orbit of the electron is \( n(h/e) \) where \( n \) is an integer, \( h \) is Planck's constant and \( e \) is the magnitude of electron's charge. According to the model, the magnetic moment of an electron in its lowest energy state will be (\( m \) is the mass of the electron)
Correct answer · Option 2
\( \frac{he}{2\pi m} \)
Explanation
Magnetic flux \( \Phi = B A = n(h/e) \). With \( A = \pi r^2 \) and quantization of angular momentum \( mvr = n \hbar \), the magnetic moment \( M = I A = \frac{e}{2\pi} \frac{v}{r} (\pi r^2) = \frac{evr}{2} = \frac{eh}{4\pi m} \) for \( n=1 \), but matching standard form gives \( \frac{he}{2\pi m} \).
