turns ratio - transformers

Simple question: which way round is the turns ratio? Google is telling me it's primary/secondary whereas the CCEA mark scheme is saying secondary/primary which, to be fair, does give the only reasonable answer for the question. One Google result said high voltage coil / low voltage coil, which seems to make sense in this context but I don't want to make an assumption based on one question.

Reply 1

AL0703

Hi, it doesn't matter which way the ratio goes as long as you're being consistent with what is on the numerator of each fraction - primary or secondary. It is usually primary coil/ secondary coil = primary voltage/ secondary voltage. However because it is a ratio you could also write secondary coil/primary coil = secondary voltage/primary voltage - you will get the same answer.