Capacitors, inductors (coils of wire), and resistors can be combined in combinations to filter or couple signals. There is a relationship between these three components and voltage and current. In a nut shell voltage and current are in phase in a pure resistance. There is no lead or lag of voltage or current in a pure resistance so they are at zero degree phase shift. In a pure inductance voltage leads the current by 90 degrees. In a pure capacitance voltage lags the voltage by 90 degrees. These phase relationships are important in electronic design/
Capacitors and inductors are reactive in that their response is frequency dependent. The way they respond in a circuits is designated XC and XL. Both are often called resistance but is impedance when XC and XL are combined with resistance. What we have is leading and lagging voltages and voltages and currents in phase. They are solved and combined with specific equations that solve for XC, XL and R. These in turn can be in series or parallel or complex circuits. A resistor is a device that resists the flow of current but although XC and XL is called resistance or impedance they are actually a voltage that opposes or aids the voltage applied to them and they are frequency responsive. Think of a batter connected in series so the voltage add up or subtract. Two 1.5 volt batter connected to aid would be 3volts but if connected to buck then would be 0 volts. When the are connect so they oppose they they are in effect a Resistance.
Combination of inductors, capacitors, and resistors can be used to couple signals or as filters. Capacitors do not actually pass a current but appears to do so by the charging and discharging of the capacitor. A voltage that varies will cause a capacitor to charge and discharge so the signal on one side of the capacitor will cause current to flow on the other side that is developed across a resistor. What we end up with is a signal on one side being duplicated on the other side. However, capacitors do not pass current which is what gives rise to the general statement that they pass AC but block DC. In reality then do not pass either.
These three simple components can be used to
Capacitors and inductors are reactive in that their response is frequency dependent. The way they respond in a circuits is designated XC and XL. Both are often called resistance but is impedance when XC and XL are combined with resistance. What we have is leading and lagging voltages and voltages and currents in phase. They are solved and combined with specific equations that solve for XC, XL and R. These in turn can be in series or parallel or complex circuits. A resistor is a device that resists the flow of current but although XC and XL is called resistance or impedance they are actually a voltage that opposes or aids the voltage applied to them and they are frequency responsive. Think of a batter connected in series so the voltage add up or subtract. Two 1.5 volt batter connected to aid would be 3volts but if connected to buck then would be 0 volts. When the are connect so they oppose they they are in effect a Resistance.
Combination of inductors, capacitors, and resistors can be used to couple signals or as filters. Capacitors do not actually pass a current but appears to do so by the charging and discharging of the capacitor. A voltage that varies will cause a capacitor to charge and discharge so the signal on one side of the capacitor will cause current to flow on the other side that is developed across a resistor. What we end up with is a signal on one side being duplicated on the other side. However, capacitors do not pass current which is what gives rise to the general statement that they pass AC but block DC. In reality then do not pass either.
These three simple components can be used to