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A series LCR circuit with R=20 , L=1.6 H and C=40 F is connected to a variable frequency a.c. source. The inductive reactance at resonant frequency is .
200
Resonant angular frequency: 0= 1 LC
= 1 1.6 40 10-6= 1 64 10-6= 18 10-3
0=125 rad s-1
XL= 0L=125 1.6
XL=200 (equal to XC at resonance; R does not matter)
Answer: 200
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