Which of the following gives the magnitude of the magnetic field at the centre of a…

PHYSICS · Single correct · CBSE · Physics · Moving Charges and Magnetism · Moving Charges and Magnetism

Problem

Which of the following gives the magnitude of the magnetic field

B

at the centre of a circular coil of

N

closely packed turns, radius

r

, carrying current

I

? (a)

B = \dfrac{\mu_0 I}{2 r}

(b)

B = \dfrac{\mu_0 N^2 I}{2 r}

(c)

B = \dfrac{\mu_0 N I}{2 r}

(d)

B = \dfrac{\mu_0 N I}{4 \pi r}