A step-up transformer increases

A step-up transformer increases

• A. Current
• B. Frequency
• C. Impedance
• D. Voltage

Answer: (D)

Transformers change voltage and current through the turns on their windings. In a step-up transformer, the secondary winding has more turns than the primary, so the output voltage rises in proportion to the turns ratio (V2 = V1 × N2/N1). Because power is roughly conserved, the higher voltage means the secondary current decreases (I2 ≈ I1 × V1/V2). The frequency doesn’t increase; it stays the same as the input. Impedance seen from the primary does change with the turns ratio, but the defining effect here is the higher voltage on the secondary.

Transformers change voltage and current through the turns on their windings. In a step-up transformer, the secondary winding has more turns than the primary, so the output voltage rises in proportion to the turns ratio (V2 = V1 × N2/N1). Because power is roughly conserved, the higher voltage means the secondary current decreases (I2 ≈ I1 × V1/V2). The frequency doesn’t increase; it stays the same as the input. Impedance seen from the primary does change with the turns ratio, but the defining effect here is the higher voltage on the secondary.