Identifying 2 Elements in an AC Circuit: R & L

AI Thread Summary
The circuit in question contains resistance (R) and inductance (L) as it shows a current lagging the voltage. Given the voltage of 120 V, frequency of 60 Hz, and a current of 6.4 A, the resistance is calculated to be 18.75 Ω. The inductance is determined using the formula L = tan(30°) * R / (ω), resulting in approximately 0.028 H. A slight variation in the calculation yields a value of 0.02869 H when using more precise digits for pi. The reasoning and calculations presented are correct and confirm the circuit's elements and their values.
zakaqel
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Homework Statement



A circuit contains only two of the three elements L,C ,R. When connected to a 120 V , 60 HZ ac generator, the current of 6.4 A lags the voltage by 30o. What are the two elements and their values?


Homework Equations





The Attempt at a Solution



given E = 120v,
f = 60Hz,
i = 6.4A,
φ =300
From the problem current lags voltage so this is a circuit containing resistance and inductance
inthis circuit , tanφ = ωL/R
R = E/i = 120/6.4 = 18.75Ω
L = tanφR/ω = tan300*18.75/2*3.14 *60 =0.028 henry


Is this reasoning correct?
 
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The technique looks good.

I get a calculated value of .02869

I used more digits of pi.
 
Thank you so much for the help!
 

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