State the characteristics of the magnetic field produced by a current - carryign solenoid sketic its magnetic field .

Explanation

A helical coil consiting of closely wound turns of insulated copper (conducting ) wire is called a solenoid .

When an electric current is passed through the solenoid , it produces a magnetic field through and around it .
The patter of magnetic field lines of the magnetic field through and around a current carrying solenoid is shown in figure 13.14

The magnetic field produced by a currnet carrying solenoid similar to that produced by a bar magnet.
(1) Directly proportional to the current I flowing through it , i.e., `B prop I`
(2) Directly proportional to the number of turns per unit length n of the solenoid i.e., `B prop n` or `B prop (N)/(l)` , where , N = total no . of turns of the solenoid and l = length of the solenoid .
(3) Dependent of the nature of the " core material " used in making the solenoid .
( Use of soft iron rod as core in a solenoid increase the strength of magnetic field ).