What is the primary characteristic of a step-down transformer?

The primary characteristic of a step-down transformer is that it decreases the voltage while increasing the current. This type of transformer is designed with more turns of wire in the primary coil than in the secondary coil. As a result, when an alternating current (AC) voltage is applied to the primary coil, it generates a magnetic field that induces a lower voltage in the secondary coil due to the ratio of the turns.

This relationship follows the principle of conservation of energy, where the power input to the primary coil equals the power output from the secondary coil (ignoring losses). Since power (measured in watts) is the product of voltage (volts) and current (amps), when the voltage is decreased in the secondary coil, the current must correspondingly increase to maintain the same power level. Thus, you get a lower voltage but with a higher current output.

The explanation for the other choices involves how transformers operate overall. For instance, a characteristic that involves increasing voltage while decreasing current refers to a step-up transformer, which operates in the opposite manner. The mention of fewer turns in the secondary coil relates to the design of step-down transformers, reinforcing the importance of the turns ratio. Lastly, a device that is used to step up current levels for transmission does