The AC circuit is shown in the following figure,
Frequency of AC source is given as
f=‌ Clearly, it is resonant frequency.
Hence,
XL=XC In this case, voltages developed across
L and
C are equal in magnitude but opposite in pollaries.
∴‌‌Z=√R2+(XL−XC)2=√R2+02
Z=R ∴‌‌I=‌=‌ Hence, the current through
R depends only on the value of
R and not
L and
C.