Question 6A243

In an ideal transformer, power in the primary (P=VI) equals power in the secondary. Therefore, VpIp = VsIs. 1. **A) Are approximately in inverse ratio to the turns ratio:** Since Vs/Vp ≈ Ns/Np (voltage ratio is proportional to turns ratio) and Ip/Is ≈ Vs/Vp, it follows that Ip/Is ≈ Ns/Np. The current ratio is indeed approximately the inverse of the turns ratio. 2. **B) Is to some extent affected by the diameter of the primary and secondary wire:** Wire diameter determines resistance and current capacity. Thicker wires have lower resistance, reducing I²R power losses in the windings. These losses mean the transformer isn't perfectly ideal, subtly affecting the actual output current and thus the observed current ratio. 3. **C) The current ratio is in inverse proportion to the voltage ratio:** From VpIp = VsIs, we can rearrange to Ip/Is = Vs/Vp. This shows the current ratio (primary to secondary) is in direct proportion to the voltage ratio (secondary to primary), or inversely proportional to the primary to secondary voltage ratio. Since all three statements accurately describe aspects of transformer current ratios, **D) All of the above** is the correct choice.