Ham Radio General Class Practice Test

What is the function of a transformer?

1. To increase or decrease voltage

2. To store electrical charge

3. To measure voltage

4. To resist the flow of current

The correct answer is: To increase or decrease voltage

A transformer is primarily designed to change the voltage of an alternating current (AC) electrical signal while maintaining the same power level (ideally). This means it can either step up (increase) or step down (decrease) the voltage based on the turns ratio of its coils. The basic operation of a transformer relies on electromagnetic induction, which allows it to transfer energy between its primary and secondary coils without a direct electrical connection. Transformers are crucial in various applications, including power distribution, where they enable efficient transmission of electricity over long distances by increasing voltage to reduce current and therefore minimize losses due to resistance in the wires. Additionally, they can be used in electronic devices to provide the necessary voltage levels for different components or circuits. Other functions mentioned, such as storing electrical charge, measuring voltage, or resisting the flow of current, are handled by different components; capacitors store electrical charge, voltmeters measure voltage, and resistors limit current flow, thus emphasizing the specific role of a transformer in voltage transformation.