Physics - EMI/AC Question with Solution | TestHub

One conducting$\mathit{\text{U}}$tube can slide inside another as shown in the figure, maintaining electrical contacts between the tubes. The magnetic field$\mathit{\text{B}}$is perpendicular to the plane of the figure. If each tube moves towards the other at a constant speed$v$, then the emf induced in the circuit in terms of$\mathit{\text{B}}$,$\mathit{\text{l}}$and$v$where$\mathit{\text{l}}$is the width of each tube, will be