Answer:
When all conductors of the same alternating-current circuit are in the same raceway, the magnetic flux around each conductor cancels out the other circuit conductors magnetic flux.
Explanation:
Whenever an alternating current flows through a conductor, a magnetic flux is produced around the conductor. The direction of the current, magnetic flux and force can be found using right hand rule.
When two conductors are placed such that the current flow is in the same direction then the magnetic flux produced in both conductors will attract each other or in other words, cancels out the effect of each other since they have equal magnitude but opposite direction.
When two conductors are placed such that the current flow is in the opposite direction then the magnetic flux produced in both conductors will repel each other.
Therefore, the correct answer is option b.
