All Problems

Electromagnetic Induction. Maxwells Equations

Problem 3.291

A thin wire ACA C shaped as a semi-circle of diameter d=d= =20 cm=20 \mathrm{~cm} rotates with a constant angular velocity ω=100rad/s\omega=100 \mathrm{rad} / \mathrm{s} in a uniform magnetic field of induction B=5.0mTB=5.0 \mathrm{mT}, with \omega \uparrow \uparrow. The rotation axis passes through the end AA of the wire and is perpendicular to the diameter AC.A C . Find the value of a line integral Edr\int \mathbf{E} d \mathbf{r} along the wire from point AA to point C.C . Generalize the obtained result.

Reveal Answer
AcEdr=1/2ωBd2=10mV\int_{A}^{c} \mathbf{E} d \mathbf{r}=-1 / 2 \omega B d^{2}=-10 \mathrm{mV}