Two wires carry different currents in the opposite directions as shown.Where is it possible for the magnetic field produced by the wires to be zero?
A)A only
B)B only
C)C only
D)A or C
E)nowhere

Question

Two wires carry different currents in the opposite directions as shown.Where is it possible for the magnetic field produced by the wires to be zero? 
A)A only 
B)B only 
C)C only 
D)A or C 
E)nowhere

Quizplus · Accepted Answer

According to the right-hand rule, the magnetic field produced by a current-carrying wire will form concentric circles around the wire. At point A, the magnetic field produced by both wires will be in the opposite direction and cancel each other out, resulting in a zero magnetic field. Similarly at point C, the magnetic field produced by both wires will be in the same direction and add up to cancel each other out, resulting in a zero magnetic field. Therefore, the correct answer is D) A or C only.

Two Wires Carry Different Currents in the Opposite Directions as Shown.Where