Question

In a rectangular loop ABCD placed in a uniform magnetic field \[\vec{B}\], the sides AB and CD are parallel to \[\vec{B}\]. The force on each of these sides is:

Options

• \[F = BIA\]

• \[F = BIb\]

• \[F = 0\]

• \[F = BIl\]

Answer 1

Since AB and CD are parallel to \[\vec{B}\], the magnetic force on each of these sides is zero. Only the sides perpendicular to the field (BC and AD) experience non-zero forces of magnitude BIb, and this pair of forces produces the torque on the loop.