Assessment and Qualifications Alliance (AQA) GCSE Physics Paper 2 Practice Exam

The number of turns on the secondary coil of a transformer directly influences the output voltage produced. According to the principles of transformers, specifically the transformer equation, the ratio of the number of turns in the primary coil to the number of turns in the secondary coil determines the relationship between the input voltage and output voltage.

When the secondary coil has a higher number of turns compared to the primary coil, it steps the voltage up, resulting in a higher output voltage. This is a fundamental principle behind how transformers are used to increase voltage levels in electrical transmission, enabling efficient power distribution over long distances. Conversely, if the secondary coil had fewer turns than the primary coil, it would reduce the output voltage, which supports lower-voltage applications.

Therefore, when a transformer has a higher number of turns in the secondary coil, it necessarily leads to a higher output voltage, making this the correct interpretation of how turns impact voltage in a transformer.