Question

If there is a circular coil having $n$ turns then the magnetic field produced is-

• A. $\frac{1}{n}$ times as that produced by single turn
• B. $n$ times as that produced by single turn
• C. $\frac{1}{n^2}$ times as that produced by a single turn
• D. None of these

Answer 1

The correct option is B $n$ times as that produced by single turn

The magnetic field is produced by current carrying wire at the centre is given by,

$B=\frac{{\mu }_{0}I}{2R}$

If there is a circular coil having $n$ turns. The field produced is $n$ times that of the single circular coil because the current in each circular turn has the same direction, so the field due to each turn will be added.

$\therefore B_{\text{total}}=n\times \frac{{\mu }_{0}I}{2R}=n\times B$