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# How does the resonant frequency affect the voltage drop across a resistor?

## How does the resonant frequency affect the voltage drop across a resistor?

For all intents and purposes, a resistor has no resonance frequency. its parasitic capacity is considered insignificant. if you speak of a resistor with a resonant circuit lc attached, it depends on how the lc is connected to the r. but in all cases, a resistor does not change the resonance frequency.

The resonant frequency is only affected by the components l and c. any r affects the degree of sharpness of the resonance.

good resistance? not at all. the concept of “resonance” only applies when you have an inductor and a capacitance, and good resistance has none.

ok, I should say ‘ideal’ resistance. every component you can make will have parasitic elements. so that a real resistance will have a certain amount of inductance and capacitance. and therefore a resonance frequency. but it is very unlikely to be significant for a frequency where you use discrete components. it is much more difficult to make a good inductor or a good capacitor (almost ideal) than to make a good resistance.

a circuit (rlc) can have a resonance, and the voltage drop across the resistor depends on the structure of the resonance circuit, for example, a parallel or series structure .

To talk about resonance, you must see a circuit as a two-port network where a voltage is applied to the input port and the output is where the resonance will appear.

If rlc is in series, then there is only one current and there is a resonance of voltage. at a certain frequency, the reactances l and c cancel each other out (short). by adding the voltages in series, v r is at its maximum.

if rlc is in parallel, then there is only one voltage between rlc and a current resonance. at a certain frequency, the reactances l and c cancel each other out (short). the voltage across l and c decreases, which reduces v r.