The magnetic dipole moment of a revolving electron (Or Magnetic Moment due to Orbital Angular Momentum): An electron revolving in an orbit about the nucleus of an atom behaves like a current carrying loop. It is called a minute current-loop and produces a magnetic field. Every current loop is associated with a magnetic moment. Magnetic Dipole Moment of a Revolving Electron Let us consider, that the magnetic moment associated with a loop carrying current $i$ and having area $A$ is: $\mu_{L}= i.A \qquad(1)$ The current due to a revolving electron is $i=\frac{e}{T}$ Where $T$- The period of revolution of electron motion around the nucleus i.e $T=\frac{2 \pi r}{v}$ $e$- Charge on an electron So from the above equation $i=\frac{e}{\frac{2 \pi r}{v}}$ $i=\frac{ev}{2 \pi r} \qquad(2)$ The area of the current loop is: $A=\pi r^{2} \qquad(3)$ Now put the value of $i$ and $A$ in equation $(1)$ $\mu_{L}= \left( \frac{ev}{2 \pi r} \right) \l

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