List of top Physics Questions on Solenoids and Toroids

Consider a long solenoid of length \(l\) and radius \(r\). If \(n\) is the number of turns per unit length and \(\mu_0\) is the permeability of free space, the inductance of the solenoid is:

Derive the expression for the magnetic field (near its centre) due to an air-filled long solenoid carrying a current $I$ and having $n$ number of turns per unit length.

The magnitude of magnetic field inside a solenoid of length 0.3 m having 800 turns carrying a current of 6 A is

a strong bar magnet is moving towards solenoid-2 from solenoid-1
In the above diagram, a strong bar magnet is moving towards solenoid-2 from solenoid-1. The direction of induced current in solenoid-1 and that in solenoid-2, respectively, are through the directions :