If current is stepped up in a transformer, what happens to voltage?

If current is stepped up in a transformer, what happens to voltage?

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

Answer: (B)

In a transformer, voltage and current are tied together by the need to conserve power. For an ideal transformer, the power in equals the power out, so V × I is roughly the same on both sides. If the current on a winding increases, the voltage on that same winding must decrease to keep that power balance. So when current is stepped up on one side, the voltage on that side drops. In contrast, when voltage increases on a step-up transformer, the current on the secondary side decreases accordingly to maintain the same power.

In a transformer, voltage and current are tied together by the need to conserve power. For an ideal transformer, the power in equals the power out, so V × I is roughly the same on both sides. If the current on a winding increases, the voltage on that same winding must decrease to keep that power balance. So when current is stepped up on one side, the voltage on that side drops. In contrast, when voltage increases on a step-up transformer, the current on the secondary side decreases accordingly to maintain the same power.