State Biot-Savarts law. Derive an expression for magnetic field at the center of a circular coil of n-turns carrying current -1.
State Biot-Savarts law. Derive an expression for magnetic field at the center of a circular coil of n-turns carrying current -1.

Ans: Biot – Savart law states that the magnetic field \mathrm{dB} due to a current element dI at any point would be as following:

    \[\begin{array}{l} \mathrm{dB} \propto \mathrm{dl} \\ \mathrm{dB} \propto \sin \theta \end{array}\]

    \[\mathrm{dB} \propto \mathrm{I}\]