What is the method for calculating turns ratio in a transformer?

The method for calculating turns ratio in a transformer is indeed based on the relationship between primary voltage and secondary voltage. The correct calculation involves comparing the primary voltage to the secondary voltage to determine how many turns are present in the primary coil compared to the secondary coil.

This can be expressed by the formula:

Turns Ratio = Primary Voltage ÷ Secondary Voltage.

In the context of transformers, the ratio of voltages will equal the ratio of the number of turns in the coils, which is fundamentally how transformers function. If the primary voltage is greater than the secondary voltage, it indicates a step-down transformer; if the secondary voltage is higher, it's a step-up transformer.

Understanding this principle is crucial for effectively using transformers in electrical systems, as it directly affects how voltage and current levels are transformed across the system. The other options either reference incorrect voltage relationships, or in the case of the option related to amps, do not pertain to turns ratio but instead focus on current ratios, which relate to the concept of power and efficiency in transformers.