MCQ
A rectangular loop carrying a current i1​, is situated near a long straight wire carrying a steady current i2​. The wire is parallel to one of the sides of the loop and is in the plane of the loop as shown in the figure. Then the current loop will:

  • A
    Move away from the wire
  • B
    Move towards the wire
  • C
    Remain stationary
  • D
    Rotate about an axis parallel to the wire

Answer

  1. Move towards the wire

Explanation:

The magnetic field due to the straight current current carrying wire decreases with increasing distance from the wire.

Thus the magnetic field is stronger at the side closer to wire and weaker at the other.

Force on each segment of wire is BIL

Hence force acting on nearer side towards the wire is greater than the force acting on farther side away from wire. Hence the net force on loop is towards the wire.

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