Question

A flat circular coil of 100 turns and radius 10 cm carries a current of 1 A. Then the magnetic dipole moment of the coil is_______ A.

Answer 1

$\text{Given}$ ; No. of turns N = 100

Radius r = 10 cm = 0.1 m

Current I = 1 A

$\text{To find}$ ; Magnetic moment $\overrightarrow{M}$

$\text{Solution}$ ;

Magnetic moment $\overrightarrow{M}$ = NI$\overrightarrow{A}$

Now area of the circular coil $\overrightarrow{A}$ = $\pi r^2$

Therfore, $\overrightarrow{M}$ = NI$\pi r^2$ = $100\times 1\times 3.14\times 0.1\times 0.1$ = 3.14

$\text{Hence the correct answer is 3.14 Wb}$