In a transformer, if voltage increases, current decreases.

In a transformer, if voltage increases, current decreases.

• A. Current decreases
• B. Current increases
• C. Current stays the same
• D. Current fluctuates

Answer: (A)

In a transformer, voltage and current are tied together by the turns ratio and energy conservation. The voltage ratio between primary and secondary follows the turns ratio, while the current ratio is the inverse of that ratio. In other words, if the secondary voltage goes up, the secondary current must go down to keep the power roughly the same (V1I1 ≈ V2I2). So when voltage increases, current decreases. Real transformers have losses, but the inverse relationship is the guiding idea.

In a transformer, voltage and current are tied together by the turns ratio and energy conservation. The voltage ratio between primary and secondary follows the turns ratio, while the current ratio is the inverse of that ratio. In other words, if the secondary voltage goes up, the secondary current must go down to keep the power roughly the same (V1I1 ≈ V2I2). So when voltage increases, current decreases. Real transformers have losses, but the inverse relationship is the guiding idea.