Consider a thin metallic sheet perpendicular to the plane of the paper moving with speed $'v'$ in a uniform magnetic field $B$ going into the plane of the paper (See figure). If charge densities ${\sigma _1}$ and ${\sigma _2}$ are induced on the left and right surfaces, respectively, of the sheet then (ignore fringe effects)
  • A${\sigma _1} = \frac{{ - { \in _0}\,vB}}{2}\,,\,{\sigma _2} = \frac{{{ \in _0}\,vB}}{2}$
  • B${\sigma _1} = { \in _0}\,vB\,,\,{\sigma _2} =  - { \in _0}\,vB$
  • C${\sigma _1} = \frac{{{ \in _0}\,vB}}{2}\,,\,{\sigma _2} = \frac{{ - { \in _0}\,vB}}{2}$
  • D${\sigma _1} = {\sigma _2} = { \in _0}\,vB$
JEE MAIN 2016, Medium
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