A variable capacitor with a range from 10 to 365 p is used with a coil to form a variable frequency LC circuit t0 tune the input to a radio.(adsbygoogle = window.adsbygoogle || []).push({});

a. What ratio of max and min frequencies may be obtained with such capcitor.

I used that [tex]\omega=\frac 1{\sqrt(LC)}[/tex] to get the ratio of max to min frequencies.

b. If this circuit is to obtain frequencies from 0.54 MHz to 1.60 mHz, the rato computed is too large. By adding a capacitor in parallel, this range may be adjused. What should the capacitance of this added be?

I said that [tex]C_{eq} = C_{old}+C_{new}[/tex]

I have to compute what [tex] C_{new} [/tex]. From part 1, I know my [tex]C_{old} [/tex]. But, how do I find [tex]C_{eq}[/tex] first? I am thinking that I have to compute that using the frequencies, but how do I get L?

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# Homework Help: Max and min frequencies of a capacitor

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