Question

LC oscillators have been used in circuits connected to loudspeakers to create some of the sounds of electronic music. What inductance must be used with a 6.7 F capacitor to produce a frequency of 10 kHz, which is near the middle of the audible range of frequencies?

Answer 1

To produce the sound, Impedance of both L and C should be equal

X_L = X_C

w*L = 1/(w*C)

w = 2*pi*f

2*pi*f*L = 1/(2*pi*f*C)

L = 1/(4*pi^2*f^2*C)

Now given that

f = 10 kHz = 10000 Hz

C = 6.7 F

So,

L = 1/(4*pi^2*10000^2*6.7)

L = 3.78*10^-11 H

Please Upvote.

Now See that in this question value of capacitance is very high and value of inductance is very low, this is very unusual in real life scenario, So please check if value of C is 6.7 F OR 6.7 F and Let me know in the comments.

If I assume C = 6.7 F = 6.7*10^-6 F, then

L = 1/(4*pi^2*10000^2*6.7*10^-6)

L = 3.78*10^-5 H = 0.378*10^-6 H = 0.378 H

Please check this one too, if first value does not work.

answered by: anonymous