Question

Why does a full loop produce a much stronger, more concentrated field at its centre than a straight wire does at an equivalent distance?

Options

• Every tiny segment contributes a field at the centre, and the loop's symmetry makes all these contributions point in the same direction

• The loop's sideways components all add, while its axial components cancel

• Only one tiny segment of the loop contributes at the centre

• The current becomes larger when the straight wire is bent into a loop

Answer 1

Every tiny segment of the loop contributes a small magnetic field at the centre. Because of the loop's symmetry, these contributions point in the same direction and build a stronger, more concentrated field.