Question

What is the formula of find resources of frequency in an ac circuit?

Answer 1

Hey mate____.
Here is your answer____.

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The only thing that I did is this:

RL=ωL=2πfL⇒f=RL2π1L=11.93Hz
cosϕ=RZ⇒Z=Rcosϕ=36.63Ω

I also don't understand how I get different results for impedance (Z) when I find it through the usual formula:

Z=R2+R2L−−−−−−−√=30.14Ω ;Z≠Z?

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