If the primary winding has 82.9 times more turns than the secondary, the turns ratio is approximately

• A. 82.9:1
• B. 1:82.9
• C. 822:1
• D. 0.012:1

Answer: (A)

The turns ratio is the ratio of primary turns to secondary turns. If the primary has 82.9 times more turns than the secondary, then Np/Ns = 82.9, which is written as 82.9:1. This also matches the ideal transformer relation Vp/Vs = Np/Ns, so the primary voltage is 82.9 times the secondary. The other options would invert or mis-scale the ratio (for example, 1:82.9 would mean the secondary has more turns, and 0.012:1 is the reciprocal of 82.9). So the correct expression is 82.9:1.