Hello!
This is not exactly a homework, but anyway.
I'm trying to figure out one thing about the circuit below.
The circuit contains two voltage sources. V1 is 5V 100Hz AC source, V2 is 15V DC source.
I know I can analyze this circuit simply treating it as if there are two currents. One is direct current, the other one is alternating current. But this is only a convenient way to analyze a circuit.
And I'm trying to imagine what's happening on a bit "lower" level.
So when AC source's voltage is increasing the current is increasing too and so more electrons are flowing through the wire. And bigger part of these electrons flow through the capacitor.
When AC source is decreasing the current though the V1 and V2 doesn't change its direction but only decreases its value because the effective voltage across the circuit decreases but still is positive (E. g. 15V  5V = 10V). But the current through the circuit branch with the capacitor changes its direction to the opposite.
What I don't understand is how the voltage drop between the point A and the ground is formed.
As I understand the voltage between point A's and the ground is
Ua = Ir2 * R2 + Ic * Xc
and
Ic = Ua / Xc
Where
Ua  point A's potentiatel
Ir2  curren through R2
R2  R2 resistance in Ohms
Ic  current through the capacitor
Xc  the capacitor's impedance
So to put this in words, the voltage drop between A and the ground depends on current through the capacitor but current through the capacitor depends on point A's voltage. And I can't understand what comes first here.
E. g. if V1's voltage is changing then as a result Ua is changing but how the circuit knows the new value of Ua if it needs Ic to determine Ua. And to determine Ic the circuit needs Ua... And so on in circles
If the question is not clear enough I will gladly clarify.
Thank you!
This is not exactly a homework, but anyway.
I'm trying to figure out one thing about the circuit below.
The circuit contains two voltage sources. V1 is 5V 100Hz AC source, V2 is 15V DC source.
I know I can analyze this circuit simply treating it as if there are two currents. One is direct current, the other one is alternating current. But this is only a convenient way to analyze a circuit.
And I'm trying to imagine what's happening on a bit "lower" level.
So when AC source's voltage is increasing the current is increasing too and so more electrons are flowing through the wire. And bigger part of these electrons flow through the capacitor.
When AC source is decreasing the current though the V1 and V2 doesn't change its direction but only decreases its value because the effective voltage across the circuit decreases but still is positive (E. g. 15V  5V = 10V). But the current through the circuit branch with the capacitor changes its direction to the opposite.
What I don't understand is how the voltage drop between the point A and the ground is formed.
As I understand the voltage between point A's and the ground is
Ua = Ir2 * R2 + Ic * Xc
and
Ic = Ua / Xc
Where
Ua  point A's potentiatel
Ir2  curren through R2
R2  R2 resistance in Ohms
Ic  current through the capacitor
Xc  the capacitor's impedance
So to put this in words, the voltage drop between A and the ground depends on current through the capacitor but current through the capacitor depends on point A's voltage. And I can't understand what comes first here.
E. g. if V1's voltage is changing then as a result Ua is changing but how the circuit knows the new value of Ua if it needs Ic to determine Ua. And to determine Ic the circuit needs Ua... And so on in circles
If the question is not clear enough I will gladly clarify.
Thank you!
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