What is the key distinction between primary and secondary coils in a transformer?

The primary coil in a transformer is fundamentally designed to receive alternating current voltage from the power source, which creates a magnetic field around it. This process utilizes electromagnetic induction to transfer energy to the secondary coil. The secondary coil, on the other hand, is responsible for delivering the transformed voltage (which can be higher or lower than the input voltage) to the load. The key distinction lies in their roles within the transformer's operation: the primary coil's role is to draw power and generate a magnetic field, while the secondary coil's role is to convert that magnetic field back into electrical energy for use elsewhere.

This distinction illustrates the transformational aspect of the device—allowing for voltage conversion while maintaining power within the system. Other options do not accurately capture this fundamental operational mechanism; for instance, stating that both coils receive input voltage overlooks the unique responsibilities of each coil. Furthermore, describing both coils as serving the same electrical function or indicating that the secondary coil stores energy misrepresents their distinct roles in a transformer’s design.