All Problems

Electromagnetic Induction. Maxwells Equations

Problem 3.312

A thin wire ring of radius aa and resistance rr is located inside a long solenoid so that their axes coincide. The length of the solenoid is equal to ll, its cross-sectional radius, to b. At a certain moment the solenoid was connected to a source of a constant voltage VV. The total resistance of the circuit is equal to R.R . Assuming the inductance of the ring to be negligible, find the maximum value of the radial force acting per unit length of the ring.

Reveal Answer
F1max=μ0a2V24rRlb2F_{1 m a x}=\frac{\mu_{0} a^{2} V^{2}}{4 r R l b^{2}}