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

Options

A. `R=20 Omega`, L=1.5 H, `C=35muF`
B. `R=25 Omega`, L=2.5H, `C= 45muF`.
C. `R= 15 Omega`, L=3.5H, `C=30muF`
D. `R=25Omega`, L=1/5H, `C=45muF`

Answer

B

Explanation

For better tuning, peak of current growth must be sharp. This is ensured by a high value of quality factor Q.
Now, quality factor is given by `Q= 1/Rsqrt(L/C)`
From the given options highest value of Q is associated with `R=15Omega`, L=3.5 H and `C=30muF`