MP Board · Class 12 · Physics · Moving Charges and MagnetismWhat is the magnetic field inside a long current-carrying solenoid?

The magnetic field inside a long current-carrying solenoid, near its center, is uniform and its magnitude is given by the formula $B = \mu_0 n I$. Here, $\mu_0$ is the permeability of free space, $n$ represents the number of turns per unit length of the solenoid, and $I$ is the electric current flowing through the turns of the solenoid. Outside the solenoid, the magnetic field is approximately zero.