# Solved Problems-9

Problems-9

**In the circuit shown in figure, find out the value of**Î¼

*R*such that the impedance of the whole circuit should be independent of the frequency of the supply. If voltage = 200 V,*L*= 0.16 H and*C*= 100**F, calculate the power loss in the circuit.**

Solution

Impedance of the inductive branch,

*Z*= (_{L}*R*+*jÏ‰L*)Impedance of the capacitive branch,

âˆ´ Impedance of the whole circuit,

In this expression, the imaginary term of the numerator is

*R*times the imaginary term of the denominator. Thus, if the real term i.e., is also*R*times the real term of the denominator i.e.*R*Ã— 2*R*, then the term consisting of w will vanish and the impedance will become independent of frequency.Thus, the condition is,

Putting the value of

*L*and*C*,Power loss in the circuit,