Which part of a step-up transformer has more turns of wire?

In a step-up transformer, the secondary winding has more turns of wire than the primary winding. This design is intentional and fundamental to the operation of a step-up transformer. When alternating current passes through the primary winding, it creates a magnetic field that induces a voltage in the secondary winding.

The relationship between the number of turns in the windings and the voltage is governed by the transformer equation, which states that the voltage ratio between the primary and secondary is equal to the ratio of the turns of wire in each winding. In a step-up transformer, since the secondary has more turns, it produces a higher voltage than the primary when energy is transferred across the transformer.

This configuration allows the transformer to increase voltage while decreasing current according to the principle of conservation of energy, which states that power (the product of voltage and current) must stay constant, barring losses. Thus, in a step-up transformer, the secondary winding's greater number of turns is essential for achieving a higher output voltage.