What is solenoid?
Solenoid is defined as:”A long tightly wound cylindrical conducting wire is called solenoid.”
Inductance of a solenoid
Consider a solenoid having n turns per unit length.When current passes through the solenoid ,magnetic field is produced inside the solenoid which is directed along the axis of solenoid.The magnetic field in space outside the solenoid is so weak that it is considered zero. The inductance of solenoid: A tightly wound cylindrical coil of wire is called solenoid. Relation for inductance of solenoid: Consider a solenoid of length l,area of cross section A having number of turns N.The magnetic field B inside a solenoid carrying a current i is given as:
B=μi ni —————(1)