How does a transformer affect the voltage of AC?

• A. It maintains constant voltage
• B. It can increase or decrease voltage
• C. It converts AC to DC
• D. It generates voltage

Answer: (B)

A transformer is specifically designed to change the voltage level of alternating current (AC) while maintaining the frequency. It operates based on the principle of electromagnetic induction, which allows it to transfer electrical energy between two or more coils of wire (windings) through a magnetic field.

When AC flows through the primary winding of the transformer, it creates a varying magnetic field, which induces a voltage in the secondary winding. The relationship between the number of turns in the primary coil and the secondary coil determines whether the transformer will increase or decrease the voltage.

If the secondary winding has more turns than the primary, the output voltage will be greater than the input voltage, resulting in a step-up transformer. Conversely, if the primary winding has more turns than the secondary, the voltage is reduced, which is characteristic of a step-down transformer.

This capability to adjust voltage levels is what makes the transformer a crucial component in power distribution systems, where voltages need to be increased for long-distance transmission and then decreased for safe use in homes and industries. Thus, a transformer can effectively increase or decrease voltage based on its design and configuration.