If you raise the tap on a transformer, what will happen to the secondary voltage?

Raising the tap on a transformer essentially changes the turns ratio of the transformer. The secondary voltage is directly related to the number of turns on the primary side compared to the number of turns on the secondary side. When you raise the tap, you are effectively reducing the number of turns in the primary winding that is utilized. This reduction leads to a decrease in the primary voltage induced into the secondary winding, resulting in a lower secondary voltage.

Transformers are designed to maintain a specific output voltage based on their turns ratio. Any alteration to this ratio can result in a corresponding change in the voltage output. In this case, by raising the tap, you reduce the effective turns on the primary side, which results in a decrease in secondary voltage.

It's important to understand that while other options might suggest different outcomes, the relationship between turns ratio and voltage output is a fundamental principle of transformer operation. Raising the tap lowers the primary input, causing the secondary voltage to decrease as outlined.