Solve Inductance Problem: 0.45 H, 120 V, 60 Hz

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To find the rms current through a 0.45 H inductor with a 2.5 Ω internal resistance connected to a 120 V (rms) source at 60 Hz, the reactance (XL) must be calculated using the formula XL = 2πfL, resulting in an inductive reactance of approximately 56.55 Ω. The total impedance (Z) of the circuit is then determined by combining the resistance and reactance, calculated as Z = √(R² + XL²). The correct rms current can be found using the formula I = V/Z, yielding approximately 0.707 A, rather than the incorrect calculation of 48 A based solely on resistance. Understanding the relationship between voltage, current, resistance, and reactance is crucial for solving such problems.
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Homework Statement



An inductor has an inductance of 0.45 H and internal resistance of 2.5 . If the H
inductor is connected to a 120-V (rms) source at 60 Hz, what is the current (rms) through
it?

Homework Equations



XL=2pi*f*L
V=IR

The Attempt at a Solution



I don't have any idea and my brain is wrecked! I'm having a difficult time finding this bridge.
 
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You don't want to use V=IR, that doesn't take into account the reactance of your inductor. For a simple LR circuit V=IZ.
 
Even using Z, I still arrive at 48 A. 120/2.5 = 48 A Which is not the correct answer. It is .7 A.
 
Last edited:
I get I = 0.707 A.
 
Z≠2.5Ω.
 
dwn said:

Homework Statement



An inductor has an inductance of 0.45 H and internal resistance of 2.5 . If the H
inductor is connected to a 120-V (rms) source at 60 Hz, what is the current (rms) through
it?
How do you determine the impedance of a series circuit of 0.45 H in series with a resistance of 2.5Ω ? You have studied complex number arithmetic?
 

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