Question

Mention the expression for the magnetic field at a point inside a toroid and explain the terms.
[ Chapter - Moving Charges and Magnetism] ​

Answer 1

Answer:

toroid is a coil of insulated or enamelled wire wound on a doughnut -shaped form made of powdered iron. A toroid is used as an inductor in electronic circuits, especially at low frequencies where comparatively large inductance are necessary.

Magnetic field due to toroid : -

∮

B

.

dl

=μ

0

I

0

∮

B

.

dl

= ∮B.dl cos0

0

=B∮dl=B(2πr)

and μ

0

I

0

=μ

0

n(2πr)I

∴B=μ

o

nI.

Thus magnetic field exists only in the tubular area bounded by the coil and it does not exist in the area inside and outside the toroid.