question_answer

  Two wires each carrying a steady current I are shown in two different configurations in column I. The magnetic field produced due to current in the wires is described in column II. Match the situations A and B in column I with all the correct statements in column II.  

Column I	Column II
	(i) The magnetic fields B at P due to the current in the wires are in the same direction.
A. Point P is situated midway between the wires above.	(ii) The magnetic fields B at P due to the current in the wires are in the opposite directions.
B. Point P is situated at the mid point of the line joining the centres of the circular wires, which have same radii.	(iii) Magnetic field at P is zero.

Answer:

                  A matches with (ii) and (iii). Applying Fleming's left hand rule, the magnetic field at P due to the current will be equal and in opposite direction,                                                B match with only (i) in column II. Applying Flemings left-hand rule, the magnetic field at P due to two currents in opposite directions will be in directions.