Electrolysis Practice Exam

What device is used to alter voltage in A.C. circuits?

1. Rectifier

2. Transformer

3. Oscillator

4. Capacitor

The correct answer is: Transformer

A transformer is the device specifically designed to alter voltage levels in alternating current (A.C.) circuits. It operates on the principle of electromagnetic induction, allowing for the transfer of electrical energy between two or more coils of wire. By varying the number of turns in the primary and secondary coils, a transformer can increase (step up) or decrease (step down) voltage while maintaining the overall power in the circuit (minus losses). Transformers are essential in electrical transmission and distribution systems as they facilitate the efficient long-distance transport of electricity by raising the voltage to reduce losses due to resistance in the wires. When the electricity reaches its destination, transformers decrease the voltage to safe levels suitable for use in homes and businesses. In contrast, a rectifier is used to convert alternating current to direct current, an oscillator generates A.C. signals at specific frequencies, and a capacitor stores electrical energy in an electric field but does not directly alter voltage levels in the way a transformer does.