Question

The change in the magnetic dipole moment associated with the orbit, at the end of time interval of the magnetic field change is,

• A. $-\gamma BQ{R}^2$
• B. $-\gamma \frac{BQ{R}^2}{2}$
• C. $\gamma \frac{BQ{R}^2}{2}$
• D. $\gamma BQ{R}^2$

Answer 1

The correct option is B $-\gamma \frac{BQ{R}^2}{2}$

$\begin{array}{c}\Delta L=\int \tau dt\\ =Q\left(\frac{R}{2}\right)\left(B\right)R\left(I\right)=\frac{Q{R}^{2}B}{2}\\ \Delta \mu =r\Delta L\\ =-\gamma \frac{BQ{R}^2}{2}\end{array}$