In a step-down transformer, how does the secondary voltage compare to the primary voltage?

In a step-down transformer, the design is specifically intended to reduce the voltage from the primary side to the secondary side. This is achieved through the use of a primary coil with a greater number of turns compared to the secondary coil. According to the principles of electromagnetic induction and transformer operation, the voltage ratio between the primary and secondary coils is determined by the ratio of the number of turns of wire in the coils.

In a step-down transformer, since the primary coil has more turns, the voltage on the secondary side will be less than that on the primary side. This characteristic makes it ideal for applications where lower voltage is required, such as adapting higher transmission voltages for safe use in residential or commercial distribution systems.

The other potential answers do not accurately reflect the functionality of a step-down transformer. The secondary voltage being equal to the primary or higher would indicate a different type of transformer, while fluctuating voltage would suggest instability or poor performance, which is not a defining characteristic of how a step-down transformer operates under normal conditions. Therefore, the appropriate understanding of a step-down transformer's operation leads to the conclusion that the secondary voltage is indeed lower than the primary voltage.