Why in an ideal situation no current flow is happening is because the oscillations between L and C "clog the wires" so to speak. They form a looping/sloshing current that does carry and contain all the energy of the system in a standing wave. A standing wave does not allow for current to pass because it traps it within itself. So the explanation for the infinite impedance is that the LC circuit @ resonant frequency creates a standing wave that takes in all the energy of the system. That is what you observe in the square-wave source with the ringing in liquid nitrogen - the standing wave just persist indefinitely. In non ideal circuits in normal conditions the additional resistance impedes creation of the perfect standing wave, so some of the energy both bleeds through and gets dissipated through heat. You are a great teacher, because of the clear though in-depth explanations that inspire me to think about those topics, even though I have only very basic formal education about electricity. You make complex topics accessible to the lay people, which is a masterful skill for a teacher to have.
Thanks. This helps a little when I’m trying to stop the signal reflectance in model railroad control systems. There are places along the track where the signal meets the reflected signal and we have a result of NO signal.
Thanks these are so well done. at 19:00 this is the reality of digital circuits at high speed, used to test TTL circuits all day and you look at pins of the ICs and what should be a square wave is like what you show, because every circuit line has L/C/R in there so this is a very important concept.
When operating at frequency where impedance are equal they alternately operate as sink and source and so can operate in isolation and the source only needs to drive current across the resistor so resistance effects prevail at determining the circuit equivalent impedance.
In my novice brain i find it counter-intuitive that at resonance the impedance is at its highest. It would seem the word resonance means the signal is at its strongest and "un-impended" from its components. It is purely resistive without any reactance. I would think adding reactance adds a kind of impeded flow to the current more so than if there was no reactance, just resistance.
Would you say this is like a car's suspension with a spring and shock absorber? they are given input waves that they resist but at other wave rates they are passive?
Yes. It's a very similar concept, where the mass/spring/damper all do calculus on the position of the car as a function of time, as they respond to disturbances. This sets up a differential equation that governs the response of the car. The spring reacts to the instantaneous vertical position, the damper reacts to the vertical velocity, and the mass responds with an acceleration. Relating it to electricity, the capacitor is analogous to the spring, the resistor is analogous to the damper, and the inductor is analogous to the mass. This means that the arrangement of capacitors, inductors and resistors, sets up a differential equation that relates the source to the load. Using the concept of impedance, and complex algebra, we're able to simplify the math from solving differential equations to solving algebraic equations.
@@carultch yes thank you, Id love to see/learn the calculus of this. but I thought the Cap is like the damper, inductor like the spring and resistor like the load/mass? Inductance is the force that resists a change in current? Capicatance the force resisting a change in voltage? the shock absorber resists in one direction far more than the other
@@bradleyr4451 One factor that probably gets in the way of seeing this analogy, is the fact that electrical engineers think in terms of current, instead of charge. By contrast, the mechanical engineers start with position, and differentiate to determine velocity and acceleration. EE's start in the middle, differentiate to find what an inductor does, and integrate to find what a capacitor does. When learning kinematics, you start at the most integrated end of the concepts, and differentiate to find everything else. Think in terms of charge on the capacitor, and the analogy will line up much better. On top of this, capacitance isn't directly analogous to the spring stiffness, but rather its reciprocal: the spring flexibility. For mechanics, the derivatives follow the following pattern: Position vs time = original function Velocity vs time = derivative Acceleration vs time = 2nd derivative For electronics, we usually think of it this way: Charge = time integral of current Current = original function Current ramp rate that an inductor acts up on = time derivative of current But instead, if you think of it this way, it will line up better with a mechanical analogy: Charge on a capacitor = original function Current = first derivative Current ramp rate for an inductor = 2nd derivative
@@bradleyr4451 The damper is analogous to the resistor, because it takes energy out of the mechanical domain, and produces thermal energy. The spring is analogous to the capacitor, because it stores energy as a function of its static configuration: the configuration of charges on the capacitor, and the configuration of metal atoms in the spring. These are both forms of potential energy, that only depend on what you can determine at a static snapshot in time. The mass of the car stores energy of motion, while the inductor stores energy in its magnetic field. If you pause everything in motion, and lose the information about current and velocity, there will not be enough information to determine the KE stored in the mass, or the energy stored in the inductor. These are both forms of energy that are based on motion, rather than position/configuration. In any event, both the energy of motion, and the energy of position, can be returned to the system reversibly. The heat energy that the resistor and damper generate, by contrast, cannot. This is why the analogy lines up this way.
@@bradleyr4451 Here's why the components have the analogous relationships I've assigned. Capacitors and springs both store energy in a potential energy form; a form that only depends on configuration of charges and atoms. You can take a snapshot in time, and you'll have all the information to know the potential energy stored in either of these components. Inductors and masses both store energy in a kinetic form; a form that depends on the state of motion of the charges and atoms. A snapshot in time won't tell you enough information to find the energy stored in these forms. Resistors and dampers do not store energy, instead they dissipate energy into the form of heat. The energy these components absorb, leaves the mechanical domain (for the suspension system) and leaves the electrical domain (for the circuit) permanently.
I found this circuit in bike indicator light, which alternately turn on and off the indicator light. But in bike it uses DC voltage, so how it's work there?
It's probably a 555 timer. There's a charge/discharge cycle of a resistor and a capacitor, that is used for establishing the clock signal. The 555 timer picks up on the time it takes for the capacitor to charge and discharge to certain fractions of the initial charging, in order to produce an output signal that cycles on and off.
Why in an ideal situation no current flow is happening is because the oscillations between L and C "clog the wires" so to speak. They form a looping/sloshing current that does carry and contain all the energy of the system in a standing wave. A standing wave does not allow for current to pass because it traps it within itself.
So the explanation for the infinite impedance is that the LC circuit @ resonant frequency creates a standing wave that takes in all the energy of the system.
That is what you observe in the square-wave source with the ringing in liquid nitrogen - the standing wave just persist indefinitely. In non ideal circuits in normal conditions the additional resistance impedes creation of the perfect standing wave, so some of the energy both bleeds through and gets dissipated through heat.
You are a great teacher, because of the clear though in-depth explanations that inspire me to think about those topics, even though I have only very basic formal education about electricity. You make complex topics accessible to the lay people, which is a masterful skill for a teacher to have.
U r true teacher of electronic. My best wishes from India .
Very nice explanation, thank you sir🌹
Thanks. This helps a little when I’m trying to stop the signal reflectance in model railroad control systems. There are places along the track where the signal meets the reflected signal and we have a result of NO signal.
Impedance mismatch in your cable/connectors.
Kindly do a practical video on EMI filter for ac mains
Thanks these are so well done. at 19:00 this is the reality of digital circuits at high speed, used to test TTL circuits all day and you look at pins of the ICs and what should be a square wave is like what you show, because every circuit line has L/C/R in there so this is a very important concept.
When operating at frequency where impedance are equal they alternately operate as sink and source and so can operate in isolation and the source only needs to drive current across the resistor so resistance effects prevail at determining the circuit equivalent impedance.
Hello, dear Sir
This video is very useful. Great explaination
brilliant have no words to say ur great
In my novice brain i find it counter-intuitive that at resonance the impedance is at its highest. It would seem the word resonance means the signal is at its strongest and "un-impended" from its components. It is purely resistive without any reactance. I would think adding reactance adds a kind of impeded flow to the current more so than if there was no reactance, just resistance.
Would you say this is like a car's suspension with a spring and shock absorber? they are given input waves that they resist but at other wave rates they are passive?
Yes. It's a very similar concept, where the mass/spring/damper all do calculus on the position of the car as a function of time, as they respond to disturbances. This sets up a differential equation that governs the response of the car. The spring reacts to the instantaneous vertical position, the damper reacts to the vertical velocity, and the mass responds with an acceleration.
Relating it to electricity, the capacitor is analogous to the spring, the resistor is analogous to the damper, and the inductor is analogous to the mass. This means that the arrangement of capacitors, inductors and resistors, sets up a differential equation that relates the source to the load. Using the concept of impedance, and complex algebra, we're able to simplify the math from solving differential equations to solving algebraic equations.
@@carultch yes thank you, Id love to see/learn the calculus of this. but I thought the Cap is like the damper, inductor like the spring and resistor like the load/mass? Inductance is the force that resists a change in current? Capicatance the force resisting a change in voltage? the shock absorber resists in one direction far more than the other
@@bradleyr4451 One factor that probably gets in the way of seeing this analogy, is the fact that electrical engineers think in terms of current, instead of charge. By contrast, the mechanical engineers start with position, and differentiate to determine velocity and acceleration. EE's start in the middle, differentiate to find what an inductor does, and integrate to find what a capacitor does. When learning kinematics, you start at the most integrated end of the concepts, and differentiate to find everything else. Think in terms of charge on the capacitor, and the analogy will line up much better. On top of this, capacitance isn't directly analogous to the spring stiffness, but rather its reciprocal: the spring flexibility.
For mechanics, the derivatives follow the following pattern:
Position vs time = original function
Velocity vs time = derivative
Acceleration vs time = 2nd derivative
For electronics, we usually think of it this way:
Charge = time integral of current
Current = original function
Current ramp rate that an inductor acts up on = time derivative of current
But instead, if you think of it this way, it will line up better with a mechanical analogy:
Charge on a capacitor = original function
Current = first derivative
Current ramp rate for an inductor = 2nd derivative
@@bradleyr4451 The damper is analogous to the resistor, because it takes energy out of the mechanical domain, and produces thermal energy. The spring is analogous to the capacitor, because it stores energy as a function of its static configuration: the configuration of charges on the capacitor, and the configuration of metal atoms in the spring. These are both forms of potential energy, that only depend on what you can determine at a static snapshot in time.
The mass of the car stores energy of motion, while the inductor stores energy in its magnetic field. If you pause everything in motion, and lose the information about current and velocity, there will not be enough information to determine the KE stored in the mass, or the energy stored in the inductor. These are both forms of energy that are based on motion, rather than position/configuration.
In any event, both the energy of motion, and the energy of position, can be returned to the system reversibly. The heat energy that the resistor and damper generate, by contrast, cannot. This is why the analogy lines up this way.
@@bradleyr4451 Here's why the components have the analogous relationships I've assigned.
Capacitors and springs both store energy in a potential energy form; a form that only depends on configuration of charges and atoms. You can take a snapshot in time, and you'll have all the information to know the potential energy stored in either of these components.
Inductors and masses both store energy in a kinetic form; a form that depends on the state of motion of the charges and atoms. A snapshot in time won't tell you enough information to find the energy stored in these forms.
Resistors and dampers do not store energy, instead they dissipate energy into the form of heat. The energy these components absorb, leaves the mechanical domain (for the suspension system) and leaves the electrical domain (for the circuit) permanently.
can someone explain why the graph of capacitive reactance v/s frequency is a straight line ?
Capacitive reactance does not linearly decrease with frequency. You need to correct that graph.
On a double-log plot, the graph will be a straight line.
@@carultch Not here, I do not see one
I agree, Xc is proportional to 1/frequency
I found this circuit in bike indicator light, which alternately turn on and off the indicator light. But in bike it uses DC voltage, so how it's work there?
It's probably a 555 timer. There's a charge/discharge cycle of a resistor and a capacitor, that is used for establishing the clock signal. The 555 timer picks up on the time it takes for the capacitor to charge and discharge to certain fractions of the initial charging, in order to produce an output signal that cycles on and off.
Pl correct capacitive reactance variation with frequency.
my head hurts