# Resonance Problem

#### testing12

Joined Jan 30, 2011
80
A parallel resonant circuit with quality factor 120 has a resonant frequency of 6​
× 10 6 rad/s. Calculate the bandwidth and half-power frequencies.

I got Bandwidth = 50 000 rad/s
w1 = 5.975e6 rad/s
w2 = 6.025e6 rad/s

Can someone please confirm? It seems for this question the back of my txt provides answers in Farads in Henrys. Its clear there was a typo.

Thanks for your help.

#### steveb

Joined Jul 3, 2008
2,436
A parallel resonant circuit with quality factor 120 has a resonant frequency of 6​
× 10 6 rad/s. Calculate the bandwidth and half-power frequencies.

I got Bandwidth = 50 000 rad/s
w1 = 5.975e6 rad/s
w2 = 6.025e6 rad/s

Can someone please confirm? It seems for this question the back of my txt provides answers in Farads in Henrys. Its clear there was a typo.

Thanks for your help.

That looks correct to high accuracy, although the upper and lower frequencies are not exactly half the bandwidth away from the center frequency in general. However, for high Q systems, the upper and lower frequencies are symmetric about the resonance to very high accuracy.