Consider a solenoid of length l and cross-sectional area A, containing N turns. The magnetic field..

Consider a solenoid of length l and cross-sectional area A,
containing N turns. The magnetic field inside the solenoid is B. What are the
coil current I and its magnetic field energy Um?

When the rate of current change with time in a solenoid is
equal to 50 A/s, a self-induced emf is generated across its ends: Ei = 0.08 V.
Find the inductance L of the solenoid.