Solution

Three identical conducting rods $L_{1}$, $L_{2}$ and $L_{3}$ are moving in different planes with the same speeds $v_{1} = v_{2} = v_{3} = 2.5\,\mathrm{m\,s^{-1}}$ as shown in the figure. The length of each rod is $60\,\mathrm{cm}$. A constant magnetic field of magnitude $B = 0.5\,\mathrm{T}$ is directed along $z$-axis. Find the magnitude of emf induced in each rod and indicate which end of the rod is positive.