Figure shows the current flowing in the coil of wire wound around the soft iron horse shoe core.

(a) State the polarities developed at the ends A and B.
(b) How will the polarity at the ends A and B change on reversing the direction of current.
(c) Suggest one way to increase the strength of magnetic filed produced.
(a) When current is passed through the windings, the end A of the arm becomes south pole (current at this face is clockwise) and the end B becomes north pole (current at this face is in anticlockwise direction).
(b) When the direction of current is reversed then the polarity will also reverse. A will become north pole (current at this face is in anticlockwise direction) and B will become south pole (current at this face is clockwise).
(c) The strength of magnetic field produced can be increased by increasing the current.