In an ideal transformer, the secondary current is inversely proportional to the turns ratio Ns/Np. Which option reflects this statement?

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Multiple Choice

In an ideal transformer, the secondary current is inversely proportional to the turns ratio Ns/Np. Which option reflects this statement?

In an ideal transformer, power in equals power out, so the voltages and currents balance with the turns. The voltage ratio is Vp/Vs = Np/Ns. Because Vp Ip = Vs Is, the current ratio is Ip/Is = Vs/Vp = Ns/Np. Rearranging gives Is = Ip × (Np/Ns). This shows the secondary current is inversely proportional to the turns ratio Ns/Np. So the statement is correct because as the turns ratio Ns/Np increases, the secondary current decreases proportionally, and vice versa. The other options don’t fit: secondary current would only equal the primary current if the turns were equal; it would be proportional to the turns ratio, not inverse; and it’s not independent of the turns ratio.

In an ideal transformer, power in equals power out, so the voltages and currents balance with the turns. The voltage ratio is Vp/Vs = Np/Ns. Because Vp Ip = Vs Is, the current ratio is Ip/Is = Vs/Vp = Ns/Np. Rearranging gives Is = Ip × (Np/Ns). This shows the secondary current is inversely proportional to the turns ratio Ns/Np.

So the statement is correct because as the turns ratio Ns/Np increases, the secondary current decreases proportionally, and vice versa. The other options don’t fit: secondary current would only equal the primary current if the turns were equal; it would be proportional to the turns ratio, not inverse; and it’s not independent of the turns ratio.

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