MCQ
A rectangular loop of wire, supporting a  mass $m$, hangs with one end in a uniform magnetic field $\vec B$  pointing into 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 decends due to a vertical force caused by the magnetic field
  • B
    The weight moves towards rightward
  • The weight rises due to a vertical force caused by the magnetic field
  • D
    None of these

Answer

Correct option: C.
The weight rises due to a vertical force caused by the magnetic field
c
$\vec F = I\overrightarrow {dl}  \times \overrightarrow B $

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