B) As the north pole of the electromagnet nears the south pole of the permanent magnet, the current reverses and the poles of the magnets then repel.
Explanation:
As we know that electric motor is based on the concept of torque due to magnetic field on current carrying coil.
Here as the current is passing through the coil the torque on the coil is given as
so here the magnetic field due to coil will continuously repelling the current carrying coil as it will move between the magnetic field so direction of current in the coil will change continuously so that it will always repel by the magnetic field and continuously rotated between the magnets
Answer:B.As the north pole of the electromagnet nears the south pole of the permanent magnet, the current reverses and the poles of the magnets then repel.
To create an electric potential difference between the ends of the conductor.
Explanation:
For current to flow, there must exist an electric potential difference between the ends of the conductor. This PD is provided by the electromotive force stored within the battery. Unless there is a connection between the terminals no PD will exist between the terminals.