LC Oscillator Tank Circuit

This electronics video explains how the LC oscillator tank circuit works. The oscillations are created by the constant transfer of energy between the capacitor and inductor of the circuit.
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[@TheOrganicChemistryTutor]

Full 1 Hour Video AC Circuits: www.patreon.com/MathScienceTutor Direct Link to The Full Video: bit.ly/3vEFYjI Physics PDF Worksheets: www.video-tutor.net/physics-basic-introduction.html Final Exams and Video Playlists: www.video-tutor.net/

[@iAbid357]

I am a computer major and I wish we had teachers like you in the electrical courses!

[@intisharalammisbahul9927]

I'm in uni doing EEE1st Yr. He helped me from IGCSE, A level and even university!

[@hoofheartedicemelted296]

I had to slow the playback to 0.75 to keep up, but it was worth it. Now I know why capacitors and inductors "oscillate". I'm so grateful for this gentleman's style of teaching ( the electronic blackboard ). If my school teachers taught in this way, I would be an engineer by now. So much would be different. But it's never too late, right? I'm off to watch The Organic Chemistry Tutor's video on "RL Circuits - Inductors and Resistors". Thanks The Organic Chemistry Tutor. Bye everyone.🖐

[@paulanderson5014]

You are good at explaining the details, thank you very much. I would like to share something that's on topic in a practical way. Years ago I spent $200 on a radio scanner so I could listen to the aircraft frequencies. Some time after that I had an idea with the LC oscillator. I payed $4 for a cheap pocket transistor radio. I opened it up and found the coil of wire near the variable capacitor (the one with the tuning knob attached). Using a small screwdriver I spread the coil apart a little which shifted the frequency of the oscillator to a range that included the aircraft frequencies. Much cheaper than $200. LOL

[@dardale9050]

Great video! Thanks for reminding your viewers you teach with holes or Conventional Flow. You explain real well!

[@AfamUgwuanyi]

I was oscillating between this video and my notes 😅. Thanks boss. You're the mvp of engineers beginning

[@cedricproper5256]

Unless I'm missing something, the feedback mechanism IS the capacitance of the mechanism minus the magnetic load. Great presentation, TOCT. Keep up the good work. Subbed.

[@nozname]

Thanks!

[@jowprower8467]

I love you man...really glad this video exists.'''

[@johnnyjohn9134]

The Best teacher!

[@erikjusufm]

I am so thankful for your channel :)

[@moftariyt4520]

Bro knows every thing 💀

[@DavidGS66]

The way to understand inductance is right hand curled fingers rule. Step 1) I creates magnetic field curling around thumb. 2) When voltage shut off, magnetic field lines are still curled around thumb, so they push I in same direction. Simple, just like a water wheel.

[@PunmasterSTP]

Thanks for helping everyone who has been studying, so that their grades don't...tank!

[@chakrasimhan2525]

Hello Sir, Thank you so much for your excellent teaching method.

[@barshanath3865]

Thank you so much for this video,sir

[@RedivivusMusic]

Love the video! How does the inductor store energy though ??

[@hackercop]

Sir am learning to build my own radios and this was really helpful thanks

[@arc-naren-ane]

In 1:16 , did the current increase because of the supporting emf produced by the inductor? Since capacitor will have lesser and lesser energy(decreasing emf(from capacitor)) because of the discharge of charges.

[@18141776hhhh]

Thank’s for sharing!

[@narendramane2727]

why inductor current starts going down after reaching max ? because once inductor is reached to max energy with max current, it starts negatively charging capacitor and due t that its current starts decreasing... this causes capacitor voltage increases and capacitor starts storing energy 0.5 CV2 form... this process repeat itself producing sustained oscillations.

[@gourabmajumdardefinitehitt8136]

You yourself gave your answer

[@krzysztofbracha6852]

Thank you bro! You asked the right question and made me think about how this really works. I think it would have been helpful to also plot and talk about the capacitor voltage / energy. At first it was not clear to me that when the current is at its peak, the capacitor voltage & energy = 0. And that the capacitor being "charged" (in 2:51) just means that the current continues to flow in the same direction but now the opposite plate will be assuming the greater amount of particles. Perhaps only I was being thick

[@flopalong4524]

I'm not sure that the inductor stores a charge. The way I understand it is that the as the voltage leads the current across the inductor, at a 90⁰ phase angle, then as the resultant magnetic field collapses, it induces a reverse EMF in the inductor windings. That's why it's called an inductor. Have I got that right? Thanks for pointing out that you were using conventional current. I find it much easier to use actual current, as it is the negative having a surplus of electrons, being attracted to the positive with a deficit of electrons. Much easier to comprehend.

[@dominicestebanrice7460]

Agreed! And I don't think it was helpful to put polarity signs on the induction coil either. This channel's video are normally masterpieces so when a little niggle arises it's noteworthy!

[@isabelescarlette2021]

Thank you , great video!

[@sethapex9670]

How would you add energy, suppose you had a DC power source like a battery, could you feed that energy into the circuit?

[@XuanNguyen-dd5ni]

The video sound is pretty good, beyond my imagination

[@vamosabv]

Thanks for the video.

[@HunzolEv]

One thing to note is the transfer of this energy back and forth between cap and inductor is almost instant or unnoticeable/travel at speed of light.

[@kabandajamilu9036]

So nice sir and when you get time help us with switch mode power supply sir

[@suhasmahesh3250]

Can you make a video on the mathematical equations explaining how the resultant current/voltage waveform is a sinusoid in the tank circuit

[@Snoopies622]

At 4:39 in diagram 4, it looks like the pluses and minuses on the capacitor and inductor are on opposite sides. Is that consistent with the convention that the voltage in a wire is constant over its length (so long as it's a region not containing a circuit element)?

[@nellvincervantes3223]

It is sine wave for current right. Then the potential difference or voltage on inductor is L*dI/dt where L is indu tance and dI/dt = rate of change of current, then I = sin(wt), dI/dt = wcos(wt). V = Lw*cos(wt). Does that mean voltage and current have 90° phase difference? Likewise for electric field and magnetic field that create electromagnetic field for signals?

[@treasuretotrash2067]

Yes i believe voltage and current are 90 degrees phase shifted.

[@periklisgewrgiou5327]

Thank you so much

[@jacobvandijk6525]

A CAPACITOR HOLDS A POTENTIAL DIFFERENCE, NOT AN ENERGY. A LOADED CAPACITOR IS LIKE A BATTERY. My batteries have a potential difference in Volts, not an energy in Joules. A LOADED INDUCTOR IS LIKE A BATTERY TOO. @ 1:22 This is the energy of the ELECTRONS being pushed by the inductor-voltage. Just like V . q = energy.

[@fatonisodiq9341]

Will you make a video about how to make that oscillation run forever, I mean until the power supply is disconnected?

[@babygreen17]

there must be some sort of feedback or external source to compensate for the loss.

[@fatonisodiq9341]

There is a lot of sketch on the internet, but i don't understand the absolute theory behind all of that

[@dremr2038]

@@fatonisodiq9341 did you find any?

[@fallu6224]

Well guess I'm the next in line in this puzzle

[@shreyasshetty2815]

Across what ur measuring current?????

[@adarsh9381]

Does the initial charging process of the capacitor use Ac or Dc? and does the current that flows alternatively across the capacitor and inductor infinitely after initial charging of the capacitor Ac or Dc?

[@whippoorwill1124]

Spoiler: we'd use a DC supply to get the initial charge into the capacitor, not an AC one. To see why, think what would happen if we used an AC supply instead. By definition the polarity of an AC supply will alternate. As long as the voltage on the capacitor is less than the supply voltage, the supply will force current into the capacitor. That will continue to charge the capacitor: the electric field between its plates will strengthen and the voltage across them will rise. With an AC supply though, that situation doesn't persist: at some point during the cycle the supply voltage will peak. It won't have reversed polarity yet, but instead of continuing to rise it will start to fall. Once it's less than the voltage which the capacitor charged up to, the supply can't keep forcing current into the capacitor. Instead the capacitor's stored charge starts draining back towards the supply. The electric field between the capacitor's plates starts to collapse and the voltage across them falls. That's not what we want if we're trying to charge the capacitor then connect it, fully charged, to an inductor in an LC tank. Instead we want to charge the capacitor, disconnect it without giving it a chance to discharge, then connect it to the inductor and watch them pass that energy back and forth. If we were quick enough, we could disconnect the capacitor right at the peak of the AC cycle: it would be fully charged and wouldn't have begun to discharge. But why make things difficult? It's much easier to use a DC supply, not an AC one, to get the initial charge into the capacitor. We'd connect the two; the capacitor would store charge until the voltage across it reached the DC supply voltage; and, because the supply voltage wouldn't start falling, we'd have plenty of time to disconnect the capacitor without it starting to discharge. Then we'd connect it to the inductor and see how they behaved.

[@abhinavdeo753]

Thank you sir

[@tayranates3611]

Can we find a transfer function representation for such circuit?

[@gennadiyfriedman9741]

So why direction of the flow keeps changing in the circuit?

[@cholyom2629]

Because inductor and capacitor change polarity over time. That means they absorb and release energy

[@akshaymugalihal5804]

Current direction keeps changing that's y

[@emadabuhagag222]

thank you

[@adithiyer9732]

Thanks, you a g

[@laxsundar]

Beautiful 😍❤️🙏🙏🙏🙏🙏

[@Cassius609]

1:50 "the current decreases" Why?

[@braaitongs]

Can you explain how tesla's hairpin circuit works?

[@michaelbradley7621]

Shouldn’t the current reverse direction when the voltage polarity over the inductor flips?

[@QuantumWithAnna]

If case 4 you have the sign of the voltage different between two points that have nothing between them but a wire. They must have the same voltage

[@martinekanji8537]

Nice one

[@successthruknowledge]

I wonder what a practical application of this circuit would be?

[@Concert_for_you]

An induction furnace in real life used in steel plants

[@arvindersingh736]

Thanks 🙏

[@عبدالرحمنالحربي-ي8د4د]

The number of molecules in a mole of any molecular substance number of ntons in one miale of any eleinent is can be biger or small or same all the time

[@dremr2038]

hey, should not the step 1 and step 4 be the same i mean like they are at the mean position. The positive side and negative side is not the way it is after one oscillation. Why?

[@NativeGatekeeper101]

Excelente profesor, voice perfect, paused, details, good. Try to tech people directly from you tube to Universities in specific hours as a TUTOR, just follow the university syllabus chapter by chapter.CONTACT UNIVERSITY FACULTY . Due to pandemics many Professor in universities are extreally lazy. They teaching NOTHING. REQUEST (AT LEAST $50,000). Create a revolutionary university learning program.

[@mykedoes4099]

Is the source "Constant Current DC " or "Pulsed DC" (THE SOURCE)

[@_A_TruongNhaNguyen]

thanks

[@dr.professour9606]

Such a voice

[@AR-vb4xy]

Sir you have yet to make a full entire video dedicated to transition metals. If you do make a video could you make it about: 1. Why transition metals are coloured. 2. Ligand-Exchange reaction explaining how ligand react with the transition metal etc There are a lot more concepts but I can't recall.

[@luigic.3508]

What’s the Power Factor on this kind of circuit?

[@rajdeva4576]

Tqs bro

[@TerribleShmeltingAccident]

what happens if you build an lc circuit with superconducting wires in a vacuum?

[@Por-poI]

In a vacuum, an LC circuit with superconducting wires would function ideally with no resistive losses, leading to perpetual oscillations of current and voltage between the capacitor and inductor. The lack of air would mean no dissipation due to the environment, and the superconducting nature of the wires ensures that the energy stored in the system remains constant unless external interactions occur. Additionally, quantum effects could emerge, especially in small-scale circuits. TLDR, it means it would run as long as you keep the machine that cools the superconductor running.

[@TerribleShmeltingAccident]

@@Por-poI ty for answering my layman questions! One more: how does the size of the circuit correlate to the emergence of quantum anomalies/effects? Is it as simply as complexity?

[@ahmedghoneem4619]

can diodes solve this damping current

[@leonardorodriguez4152]

Hi, very nice video! Could you please provide concrete examples for both the capacitor and the inductor to show the undamped oscillations? I am asking for the values of capacitance and inductance. I would like to charge the capacitor by means of a regular 6 V battery, and I would like to see the oscillating current on one oscilloscope screen. Also, which energy feedback would you recommend having connected to this “Tank” circuit in order to keep the amplitude moderately constant? Thanks for your attention to this!

[@nugget9245]

Back and forth. Back and forth. 🤣

[@TaiburRahmanKhan664]

👍

[@hackercop]

Subscribed but please don't use Comic sans

[@TGDPD]

you great

[@Rem1061]

Hate to tell you but the current flow is from the negative to the positive.

[@yashwant7276]

Go and watch SpongeBob SquarePants

[@nellvincervantes6233]

That is electron flow. Conventional current is opposite where you take the charge of electrons as positive.

[@dremr2038]

@@nellvincervantes6233 hey, should not the step 1 and step 4 be the same i mean like they are at the mean position. The positive side and negative side is not the way it is after one oscillation. Why?

[@lurium2042]

@@dremr2038 yep, I think he just made a mistake!!! 1 and 4 diagram should be the same, it's only the floors of the current that changes.

[@TopAhmed1]

@@dremr2038 yeah man I am gonna leave this video, that confused me also

[@PhysicsClasses-123]

N

[@ayandamaphumulo5637]

Type shii

[@DeeegerD]

Incomplete

[@TwistedKrizZ33]

thank you