What is a solenoid? Draw a sketch of the pattern of field lines of the magnetic field through and around a current carrying solenoid.

Question

(i) What is a solenoid? Draw a sketch of the pattern of field lines of the magnetic field through and around a current carrying solenoid. 

(ii) Consider a circular loop of wire lying in the plane of the table. Let the current pass through the loop clockwise. Apply the right hand rule to find out the direction of the magnetic field inside and outside the loop.

Answer 1

(i) (a) A solenoid is a long coil containing a large number of close circular turns of insulated copper wire in the form of a cylinder. 

(b) The magnetic field produced is similar to that produced by a bar magnet. Pattern of magnetic field lines due to a current carrying solenoid:

(ii) Since the current passes through the loop is clockwise, therefore, the front face of the loop will be the south pole and the back face, i.e., the face touching the table will be north pole. According to right-hand rule, the direction of magnetic field inside the loop will be pointing downward. In outside the loop, the direction of magnetic field will be upward.