Question

The magnetic field inside a toroid is B. If n are the number of turns in unit length of the toroid is n and I current is flowing in the toroid then magnetic field outside the toroid will be:
(a) B
(b) \(\frac{B}{2}\)
(c) Zero
(d) 2B

Answer 1

(c) Zero
There is no current flowing in external loop so B = 0