Question

Two identical coaxial circular coils carry the same current 1 amp but in opposite directions. The magnitude of the magnetic field \( B \) at a point on the axis midway between the coils is

• A. \( \text{Zero} \)
• B. The same as that produced by one coil
• C. Twice that produced by one coil
• D. Half that produced by one coil

Hint:

Equal and opposite currents in symmetric coils produce zero net magnetic field at the midpoint.

Answer 1

The Correct Option is A

When two identical coaxial coils carry equal currents in opposite directions, their magnetic fields at the midpoint on the axis cancel each other due to symmetry. Hence, the net magnetic field at that point is zero.