**Understanding Capacitors: A Beginner's Guide**

If you've ever had the problem of your monitor or TV suddenly stopping work at some points, there's a big chance that you can repair it by replacing the dodgy capacitors on the circuit board. In fact, almost every circuit of consumer electronics has such capacitors in one form or another.

In this article, we'll talk about what a capacitor is, what the ratings on it mean, and what function it fulfils in our circuits. We'll also explore how to build a simple capacitor ourselves and delve into its behavior in DC and AC circuits.

**What is a Capacitor?**

To understand some fundamentals of capacitors, it would be best to build one yourself. I used an aluminum sheet and made one line in the middle of the material, another line at 1/3 of the length of the other side. Then, I used my saw to cut out four pieces and used my clamps to position the two smaller pieces parallel to each other with a very small distance. This is basically a capacitor.

The wiring symbol looks like this: if you hook it up to a 30-volt power source by connecting plus to one side and minus to the other, you can see that just for a fraction of a second, a very small amount of current flows. This current is also known as electron flow, which charges up the plates by creating an electrostatic field between them.

**How Does a Capacitor Work?**

When we measure the capacitance of our homemade capacitor, we see that it's around 50-60 picofarads. That's nothing, and in fact, the capacitor cannot even hold a charge when I disconnected from the power source. Normally, capacitors do this and can supply stored energy from the electrostatic field just like a battery can supply power.

However, the more capacitance and maximum voltage rating it has, the more power it can deliver. Now, let's get back to our plate capacitor. We can actually improve the capacitance by increasing the surface of the plates. This way, there are smaller spaces for electrons, and thus, a bigger electrostatic field is created.

If we get the plates even closer to each other so they're touching, we can also increase the capacitance. Since the force on the electrons to the positive plate increases, there's more space for other electrons. However, we're still only at 110 picofarads with the big plates. To improve this even further, we can add a dielectric material like distilled water in the middle of the plates.

**Adding Dielectric Material**

The H2O dipoles line up with the electrodes static fields and increase the force on the electrons, which again creates more space for others. I was even capable of creating a 2.5 microfarad capacitance like this, which is not bad!

This is basically how all capacitors work in one way or another. If we take apart a real-life example like this electrolytic capacitor, we can see it also just contains metal films with a dielectric material in the middle.

**Behavior in DC and AC Circuits**

Now that we've explored what capacitors are and how they work, let's move on to how they behave in DC and AC circuits. For this, you might want to watch my inductor coils video before hand since there are many relations between those two.

First of all, let's take a look at switching operations. This time, the voltage of a capacitor cannot change instantly because it needs to build up its electrostatic fields or turn it into another kind of energy. However, the current will change immediately and slowly decrease while the capacitor reaches its maximum voltage.

This is used to keep voltages at a stable level at the output of your power supply or to decouple an IC in your circuit. We can also use them in combination with a resistor to charge them up in a specific time. This way, they can be used to create different signals like a square wave with this Pi 5 timer.

**Capacitor and Frequency**

If we move over to AC signals with the sine wave, we can also find out that a capacitor just like a coil creates another form of resistance called capacitive reactance. However, in contrast to coils, the capacitive reactance decreases as frequency increases.

To be more precise, the formula for capacitive reactance is 1/(2πfC), where f is the frequency and C is the capacitance. This means that the higher the frequency, the lower the capacitive reactance will be.

**Capacitor in Parallel**

Now, let's talk about how to compensate our inductive load with a capacitor in parallel. When we add a capacitor in parallel to an inductive load, it also creates a phase shift but in the opposite direction. This compensates our inductive load and relieves the power grid from the reactive power.

And with that being said, you already know quite a lot about capacitors. I hope you like this video! If so, don't forget to share and subscribe. That would be awesome!

Consider supporting me through my Patreon campaign to keep such videos coming. Stay creative, and I will see you next time!

WEBVTTKind: captionsLanguage: enIf you ever had the problem that your monitor or TV just stops working at some pointsThen there's a big chance that you can repair it by replacing the dodgy capacitorson the circuit board and when you think it almost every circuit of consumer electronicsHas such capacitors in one form or another?so in this videoLet's talk about what a capacitor is what the ratings on it means and what functions he fulfils in our circuits?Let's get startedIn order to understand some fundaments of capacitors it would be the best to build one ourselvesI used this aluminum sheet and made one line in the middle of the material andanother line at 1/3 of the length of the other sideThen I used my saw to cut out my four pieces and use my clamps to position the two smallerParallel to each other with a very small distance and that is basically a capacitoreven the wiring symbol looks like this if I hook it up to a 30 volt power source by connecting plus to one sides andMinus to the other we can see that just for a fraction of a second a very small amount of current flowingThis currents AKa Electron flowcharged up the plates by creating an electron on the negative side andThus an electrostatic field is created between the platesWhich stores our electric energy if we measure the capacitance? We see that it is around 50 60 picofaradsThat is nothing and in my the capacitor cannot even hold a charge when I disconnected from the power sourceNormally they do this and can supply the stored energy from the electrostatic field just like a battery can supply powerjust way way less power the more capacitance andMaximum voltage rating it cuts the more power it can deliver now back to our plate capacitorWe can actually improve the capacitance by increasing the surface of the platesThis way there are small space for electrons and thus a biggerElectrostatic Fields and if we get the plates even closer to each touching them we can also increase the capacitanceSince the Force on the electrons to the positive plateIncreases and the stairs again more space for other electrons, but we are still only at110 picofarads with the big plates to improve this even farther we can also add a dielectric materialLike distilled water in the middle of the platesthe H2ODipoles line with the electrodes static fields and increase the force on the electrons which again creates more space for others I?Was even capable of creating a 2.5 micro farad capacitance like this which is not bad?This is basically how all capacitors work in one way another if we take apart a real-life examplelike this electrolytic capacitorwe can see it also just contains of metal films with a dielectric material in the middle andSince the Metal is very close to each other and the dielectric material is certainly not a perfect isolatorThere's always a voltage limit givenEverything above has the potential to create a spark over and thus destroying your capacitorAnd it's also important to not reverse the polarity of the electrolytic ones. They surely don't like that as welllet's move on to how they behave in DC and AcCircuits and for this you might want to watch my inductor coils video before hands since there are manyRelations between those two first of all let's take a look at switching operationsthis time the voltage of a capacitor cannot change instantlyBecause it needs to build up its electrostatic fields or turn it into another kind of energyBut the current will change immediately and will slowly decrease while the capacitor reaches its maximum voltageThis is used to keep voltages at a stable level at the output of your power supplyOr to decouple and IC in yourWe can also use them inCombination with a resistor to charge them up in a specific time this way they can be used to create different signalslike a square wave with this Pi 5 timer if we move over to Ac signals with the sine waveWe can also find out that a capacitor. Just like a coil creates another form of resistanceCalled Capacitive reactanceBut in contrast two coils the capacitance and frequency is in direct proportional to the of reactancethat means if I decrease the capacitorLess current will flow and this way our led will not light very much anymoreAnd if I decrease the frequency, it's the same less current will flowthe final formula for the capacitive reactancelike this since we know that this is basically a frequency based resistorwe can easily build our C filters which keep certain low frequencies out orcertain high frequencies out and there is no big difference betweenRl and RC filters you usually use our sieve becauseCapacitors are mostly cheaper and small in comparison to coilsLastly let's hook up our microwave motor to our power lineAnd we see that it still creates a phase shift up around 36 degrees as I told you beforeThis creates reactive power which strains our power grid in order to get rid of this we can add a capacitor in ParallelWhich also creates a phase shift but in the other direction?This compensates our inductive load and relieves the power grid from the reactive power and with that being saidYou already know quite a lot about capacitors. I hope you like this video. If so don't forget to share and subscribeThat would be awesomeConsider supporting me through my patreon campaign to keep such videos coming stay creativeAnd I will see you next time