Obtain the expression for the magnetic energy stored in a solenoid in terms of magnetic field B, area A and length l of the solenoid.

Derive the expression for the magnetic energy stored in a solenoid in terms of magnetic field B, area A and length l of the solenoid carrying a steady current 1. How does this magnetic energy per unit volume compare with the electrostatic energy density stored in a parallel plate capacitor ?

Starting from the expression for the energy W=1 // 2 LI^(2) , stored in a solenoid of self-inductance L to build up the current I, obtain the expression for the magnetic energy in terms of the magnetic field B, area A and length l of the solenoid having n number of turns per unit length. Hence, show that the energy density is given by B^(2) // 2mu_(0) .

Strating from the expression for the energy W=(1)/(2)LI^(2) , stored in a solenoid of self-inductance L to build up the current I, obtain the expression for the magnetic energy in terms of the magnetic field B, area A and length l, of the solenoid having n number of turns per unit length. Hence show that the energy density is given by B^(2)//2mu_(o) .

The magnetic field inside a solenoid is-