MCQ
A rectangular loop of wire, supporting a mass $m$, hangs with one end in a uniform magnetic field $\overrightarrow B $ pointing out of the plane of the paper. A clockwise current is set up such that $i > mg/Ba$, where $a$ is the width of the loop. Then
  • A
    The weight rises due to a vertical force caused by the magnetic field and work is done on the system
  • B
    The weight do not rise due to vertical for caused by the magnetic field and work is done on the system
  • The weight rises due to a vertical force caused by the magnetic field but no work is done on the system
  • D
    The weight rises due to a vertical force caused by the magnetic field and work is extracted from the magnetic field

Answer

Correct option: C.
The weight rises due to a vertical force caused by the magnetic field but no work is done on the system
c

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