Conservation of Energy

The correct answer is option C, conservation of energy. This is because the law of conservation of energy states that energy cannot be created or destroyed, it can only be transferred or transformed from one form to another.

When an induced electromotive force (emf) is produced due to a change in magnetic flux, it creates a current in a circuit. The direction of this current depends on the direction of the change in magnetic flux and the polarity of the induced emf.

If the polarity of the induced emf is such that it tends to produce a current which aids the change in magnetic flux that produced it, it means that the induced emf and the change in magnetic flux have the same direction. This indicates that the energy is being supplied to the circuit, rather than being conserved.

Explanation:

- Induced emf: When there is a change in the magnetic field through a coil of wire, an induced emf is produced. This can be due to various factors such as changing the magnetic field strength, changing the area of the coil, or changing the orientation of the coil with respect to the magnetic field.

- Change in magnetic flux: Magnetic flux is a measure of the number of magnetic field lines passing through a surface. When there is a change in the magnetic field or the area of the surface, the magnetic flux changes. This change in magnetic flux induces an emf in a coil of wire.

- Polarity of induced emf: The polarity of the induced emf depends on the direction of the change in magnetic flux. According to Faraday's law of electromagnetic induction, the induced emf is such that it opposes the change in magnetic flux. This is known as Lenz's law. However, in some cases, the induced emf can have the same direction as the change in magnetic flux.

- Conservation of energy: Energy is a fundamental concept in physics and is conserved in all physical processes. The law of conservation of energy states that energy cannot be created or destroyed, it can only be transferred or transformed from one form to another.

- Violation of conservation of energy: If the polarity of the induced emf is such that it tends to produce a current which aids the change in magnetic flux that produced it, it means that energy is being supplied to the circuit. This violates the law of conservation of energy, as energy is not being conserved but rather being added to the system.