Inductance of a Solenoid. A long, straight solenoid has N tums, uniform cross-sectional area A, and length I. Show that the inductance of this solenoid is given by the equation L = µoAN2/l. Assume that the magnetic field is uniform inside the solenoid and zero outside. (Your answer is approximate because B is actually smaller at the ends than at the center. For this reason, your answer is actually an upper liroit on the inductance.)