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pious&peevish
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My textbook doesn't cover transformers in very much detail at all, so I only have a very vague idea as to how they work...
The secondary voltage of an ignition transformer in a furnace is 13.9 kV. When the primary operates at an rms voltage of 120 V, the primary impedance is 22.6 Ω and the transformer is 91.1% efficient.
a) What turns ratio is required?
b) What is the current in the secondary?
c) What is the impedance in the secondary?
V2/V1 = N2/N1 (where N2/N1 is the turns ratio)
V1 * I1 = V2 * I2
V1/I1 = R/(N2/N1)^2
I already solved a) correctly, which was just 13.9 kV/120 V (i.e. N2/N1). But besides that, I honestly don't know what else to do. I guess I could start by plugging in 22.6 ohms into the equation for impedance [i.e. I(rms) = V(rms)/Z], but I'm getting completely mixed up. I'm also not sure how efficiency affects the final result...
Homework Statement
The secondary voltage of an ignition transformer in a furnace is 13.9 kV. When the primary operates at an rms voltage of 120 V, the primary impedance is 22.6 Ω and the transformer is 91.1% efficient.
a) What turns ratio is required?
b) What is the current in the secondary?
c) What is the impedance in the secondary?
Homework Equations
V2/V1 = N2/N1 (where N2/N1 is the turns ratio)
V1 * I1 = V2 * I2
V1/I1 = R/(N2/N1)^2
The Attempt at a Solution
I already solved a) correctly, which was just 13.9 kV/120 V (i.e. N2/N1). But besides that, I honestly don't know what else to do. I guess I could start by plugging in 22.6 ohms into the equation for impedance [i.e. I(rms) = V(rms)/Z], but I'm getting completely mixed up. I'm also not sure how efficiency affects the final result...