Calculating Resistance and Input Voltage in an RL Circuit with AC Generator

AI Thread Summary
To find the resistance R in the RL circuit, the current I can be calculated using the formula I = ξ / √(R² + X²), where ξ is the total voltage. The inductive reactance X is determined using X = ωL, with ω being the angular frequency (2π times the frequency). The calculated total AC input voltage is V = √(40² + 30²), which equals 50V, confirming the voltage across the inductor and resistor. The discussion highlights the need to correctly apply the formulas for current and voltage in RL circuits. Understanding these calculations is essential for solving similar problems in AC circuit analysis.
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Homework Statement



A resistance R and a 1.4 H inductance are in series across a 60 Hz AC voltage. The voltage across the resistor is 30V and the voltage across the inductor is 40V.
(a). What is the resistance R ?
(b). What is the AC input voltage ?

Homework Equations



\xi=I*Z

The Attempt at a Solution



(a).So far I have I=\xi/ \sqrt{}R^2+X^2

How do I proceed from here ? Do I use I= \xi/ \omegaL to find the current then substitute back to the first equation to solve for R ?

(b). I calculated V=\sqrt{}40^2+30^2=50 V. Is this correct ?
 
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I mean X(L)^2 not XL^2
 
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