Which of the following combinations should be selected for better tuning of an LCR circuit used for communication ?

Options

A. `R=20 Omega, L=1.5 H , C=35 muF`
B. `R=25 Omega, L=2.5 H , C=45 muF`
C. `R=15 Omega , L=3.5 H, C=30 muF`
D. `R=25 Omega , L=1.5 H, C=45 muF`

Answer

C

Explanation

Q factor for an L-C-R circuit is given by
`Q=1/R sqrt(L/C)`
where R = resistance, L = induction, C = capacitance
For better tuning of an L-C-R circuit, quality factor of the circuit must be as high as possible. For this R should be low, L should be high and C should be low.