Magnetic Field of a Solenoid
Mohan tightly wound a very long copper wire on a PVC pipe and carefully took the pipe out. The two ends of the copper wire then attached to a battery.
This cylindrical shape of copper wire showed few properties of a bar magnet. Later he found that it is called a solenoid and this solenoid is used in several devices such as door bell, relay switch etc. The magnetic field of a solenoid is given below.
The magnetic field strength of a solenoid having n turns is `B=mu_0nl`, where, `I` is the current flowing in the solenoid.
The magnetic field outside a solenoid is
Options:
(a) infinity
(b) zero
(c) double the value of field inside
(d) half the value of the field inside