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Nice work. Thank you. New generation is very lucky. When I was an engineering student (30 years ago) we had only paper, pencil, books and blackboard. These kind of videos should be considered as a big revolution in education.
Yeah, I remembered how much trouble I did when I was 14 years old (in 1993) trying to have a comprehension of all those electrical phenomenon that are very easy to understand using animations nowadays.
I agree that this videos are astonishing useful and beautiful. However, there're evidence (my apologies for not find the source; I explain it below) that images associated with text are as good as animations, if not superior. This phenomenon is related with "brain effort" to learn the schema, concept or principle. I remember Derek Muller (Veritasium) discuss it in one of his videos, but as I search through his channel, I couldn'r find it. It is in one of his videos about education and learning. Edit: found it --> ruclips.net/video/GEmuEWjHr5c/видео.html
Except water flowing in pipes is usually a non-linear relationship between flow rate and pressure drop, so it is more difficult to make the analogy mathematically accurate.
carultch. Not only that. The electric phenomena is tridimensional, happens in the space around the circuit. At any given instant half of the energy is in the space and half in the circuit. Actually the energy is flowing from the battery to the space and from the space to the conductor. The Voltage, the electric force, is not like a pressure pushing the electrons, the Voltage is a field in the space. The magnetic field is not a waste product of the electrons movement, magnetic field stores energy in the space! The energy is flowing from the space to the wire perpendicularly.
That's quite important... A lot of people use pipes to make analogy for electricity, which seems to be extremely convenient at first, but I think that now I understand why I wasn't able to grasp the concepts of electricity fully... Thanks!
I recently created a Patreon account for people who want to help support my channel. The link is on my RUclips home page and in the video description up above. Also, in case, you have not already seen them, I uploaded several other videos recently. As always, for each video that you like, you can help more people find it in their RUclips search engine by clicking the like button, and writing a comment. Lots more videos are coming very soon. Thanks.
+Eugene Khutoryansky These are such amazingly high quality videos. I'm shocked at how many high quality, illustrative videos you have on your channel. I'll see if I can donate a bit to your patreon account :). Keep up the awesome work. Mathematics and sciences are, in my humble opinion, the most beautiful and fulfilling study that one can engage in. Thanks for making it accessible to the massive amount of scientifically illiterate people.
+Eugene Khutoryansky I don't know what a patreon account is; but your videos have always been amazing and I think it's well worth donating a few bucks for all the value I get out of your channel.
+Physics Videos by Eugene Khutoryansky Your videos on electric circuits are awesome. I use them on a regular basis and my students love them. They really help to re-enforce what the text book is saying. Is it possible to make a video on Alternating Current and Alternating Current Circuits. The future Aircraft Technicians would greatly appreciate this.
+Physics Videos by Eugene Khutoryansky All the equations for physics are dependant to physical parameters. The viscosity, thermal conductivity, electrical conductivity and speed of light depend on the medium. Thus, ohm's law is correct, but one must apply differential form of equation to solve complex problems, not simplified form that is constant parameter solution of ohm's differential law.
OMG! I've been studying all this stuff on my own and when I started investigating concepts around Resistance I came to a similar idea about the fallacy but couldn't articulate it since I didn't know enough. I'm so greatful that this video goes into it because I thought I was crazy lol!
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Exactly, even the voltage varies with the variation of the external resistance, due to the internal resistance of the real generator, the ohm law must be interpreted assuming the ideal case, the real case can always be traced to the summation of the ideal cases. Ohm's law is essential for calculating the circuit because it is very close to the ideal case.
I really thank you. Your video is a simple and clear illustration of how voltage, resistance and current intensity interact. One can watch it OBSERVE, SEE how it works clearly. You are helping lots of people to really understand the basics of electricity. Thank you.
"There are many examples in logic where a statement is always true simply because of the way in which we created our definitions for the words, and the statement doesn't actually tell us anything about the external world around us.This one of the logical fallacies we need to watch out for, both with regards to science and also with regards to life in general." Boom.
@@naveensundar4765 Let's look at the statement that immediately precedes that one: "The fact that the number that we get at any given time is always equal to the resistance of the material is simply due to the fact that this is how we defined the word 'Resistance' in the first place." Let's say we had workers packing apples in a factory. We can create a value for each worker called "productivity" (P), which is the number of apples (A) they packed in a given period of time, divided by the number of hours that they worked (T). P = A / T A worker whose productivity is 500 can pack 500 apples in one hour (seems pretty slow, but we'll ignore that). Next, we make an observation: if we know a worker's productivity (P), then we can predict how many apples (A) they can pack in a given amount of time (T). A = PT This is a valid observation, however we haven't actually learned anything. P was already derived from A and T, so deriving A from P and T doesn't tell us anything new about the nature of our factory. At best, in this exercise we have learned about the multiplication property of equality, which allowed us to re-arrange the factors to solve for a different variables. In which case, we've learned something new about math, but not about apples, time, or productivity. I believe Khutoryansky was referring to circular logic. For example, a society might decide that drinking alcohol is immoral, so they make a law against it. Now it is illegal. It is illegal because it is immoral. Now, imagine someone new enters the society, and they discuss alcohol with some of the locals. "If you like to drink alcohol, we will not accept you as a friend. Drinking alcohol is wrong." "Why is it wrong?" "Because it is illegal. Only an immoral person would want to do something that is illegal." Then it isn't a discussion about alcohol at all. They are simply deriving immorality from illegality, when illegality was originally derived from immorality. This is a closed loop, where no new information is allowed out or in. In fact, we can't trace the origin of the "immorality" label for alcohol. How did it come to be immoral in the first place? "The Law of the Immorality of Alcohol", then, isn't a new law in the scientific sense. It's just a logical derivation of the previous "The Law of the Illegality of Alcohol". I believe this was the intended point. Not specifically about alcohol, of course.
@@tom_something What about the equation for force then? Consider a mass, M, falling near earth's surface at acceleration g. We define force: F=Mg. But what if we did not actually know g, for whatever reason, and we knew M and F, then we could 'learn something new about the world' by finding g from g=F/M. But... Do we really learn something about the external world or just a construct of ours? We like to think of a force as a property of the physical world but that is ultimately based on acceleration and mass, and acceleration is based on time and velocity, which is based on position. The only 'tangible' things here are perhaps position, mass, and time. Does this make velocity, acceleration, and force a construct that is just as invented as resistance?
@@Nelson-sr2bi Yes, in fact. Something that would qualify as an actual law of physics would be, say, the Law of Conservation of Momentum, or the Law of Conservation of Energy. Neither of those laws are derivable from our definitions of momentum or energy (p = mv or e = 1/2mv^2 as an example), or are they definitions of some other variable. Those laws genuinely tell us something about the universe, which is what separates them from simple definitions like F=ma. By the way, just because we chose to define things like velocity and acceleration doesn't mean that they aren't real. After all, the laws I mentioned actually rely on our definitions of mass and velocity to be meaningful.
The mentioned fallacy states that a law which has been formulated is a mathematical representation for a model that describes something observable in the real world. That one model works together with all the other models may seem like a coincidental happenstance to critics of science, but it actually is a beautiful hint that the 'laws' are just implications of higher abstractions. Some people say scientists act like there is only one truth and they know it. Maybe some scientists are that way. But the truth is, scientists just state that their model works and fits in the picture.
When showing a higher or lower value of resistor may be better by lengthening or shortening rather than make the resistor a smaller diameter for a smaller resistance; because typically a smaller diameter resistor does not indicate less resistance but more resistance. I also agree with a previous comment of "but that doesn't mean that the voltage drop across a ckt element is not proportional to the current flowing through it " Thank you for your animation and will looking for to an update.
Not only are these videos perfect visual presentations, but the final thoughts of this particular video was almost existential. :) Love your work, thanks.
Ohm's observation was that the apparent Potential drop across an ideal Resistor is proportional to the Current through it. So, V=RI would be the linear model accounting for V versus I data. Yet, one uses I-V characteristics, which gradient equals 1/R (conductance). This tells us how fast the charge transport can be through the Resistor. Hence, Resistance is a measure of the charge transport time! *R ~ t* Yet, in a real _ohmic_ resistor, temperature might increase with time, so the I-V slope changes, depending on the experimental procedure...
+Blackyisacat, I am glad that these videos are getting to you in time. In the past, I had a person complain that the video was on a topic that he had just taken his final exam in, and that if the video had been released just a few days earlier, it would have helped him correctly answer the question that he missed.
Ive spent hours upon hours trying to understand resistance and get an intuiative feel about how it worked and this video is the only one that got me to figure it out.
Totally love your videos, they take something that may seem so abstract at first and turns it into a concrete and visual explanation that is incredibly helpful when studying physics. Thanks again!
Hi Eugene, during my studies in high school I would have needed these kind of representations of how electicity works. Now, all thank to you, I can put images and representations on what I know of electricity, and it makes way more sense
i have multiple accounts, and multiple times i would find your videos for mutiple reason. And, in all of those scenarios, i would like, subscribe and thank you. So here i am again: Thank you.
Khutoryansky's definition: "Physical laws tell us how the Universe works." ( 3:27 ) Ohm's Law tells us that the resistance of an object at a certain time is equal to the voltage across the object at that time divided by the current through the object at that time. Because of Ohm's Law, if you know two of the three values (1. Resistance 2. Voltage 3. Current) for a certain object at a certain time, then you can calculate the third value of the object at that time. It is possible to calculate and consequently know the third value because Ohm's Law tells us how the three values work in the Universe. Ohm's Law tells us how a part of the Universe works, and thus is a law by Khutoryansky's definition of a physical law. The Universe works in way that when the resistance of an object changes (whether by temperature or some other change in the object), current through the object changes because the voltage across the object remains the same. Ohm's Law tells us about this way that the Universe works. "the statement doesn't actually tell us anything about the external world around us." ( 5:29 ) The statement of Ohm's Law tells us how the resistance of an object, the voltage across the object, and the current through the object are related, like how the equation F = ma (Newton's Second Law) tells us how the force applied to an object will relate to the mass of the object and the acceleration of the object caused by that force. "There are many examples in logic where a statement is always true simply because of the way in which we created our definitions for the words, and the statement doesn't actually tell us anything about the external world around us." ( 5:19 ) F = ma is always true because we have defined force as a thing measured in joules where 1 joule = 1 kg * 1 m/s^2, so of course X joules will equal Y kg * Z m/s^2. My first two paragraphs apply the same way to Newton's Second Law. Read them with the terms replaced: [Newton's Second Law] tells us that the [force applied to an object] is equal to the [mass of the object] [multiplied] by the [acceleration of the object caused by that force]. Because of [Newton's Second Law], if you know two of the three values (1. [Force] 2. [Mass] 3. [Acceleration]) for a certain object at a certain time, then you can calculate the third value of the object at that time. It is possible to calculate and consequently know the third value because [Newton's Second Law] tells us how the three values work in the Universe. If I am missing something, please explain. I will try my best to understand.
+Blake Callahan, in the case of F = mA, force is defined independently of this equation. For example, we have laws for how forces on charged particles are generated as the result of electric and magnetic fields. On the other hand, in the case of R=V/I, resistance is defined entirely by this equation. F=mA relates how something which already has a definition (force) relates to other observable quantities. On the other hand, R=V/I does nothing other than to just create a definition for the quantity "V/I".
+Blake Callahan, in the case of an electromagnetic force, we have F = q[E + v x B]. This is just one example, as other types of forces have other equations.
+Eugene Khutoryansky I'm not sure I understand your logic regarding what makes a law. Newton tells us force is the time derivative of momentum. That's true, according to him. Then, we find other ways to calculate force, as you pointed out in your comment. But wouldn't it just be another way to calculate the time derivative of momentum? If you say Ohm's law is not a law because resistance is only a way to define V/I, wouldn't force just be another way to define dp/dt, thus making it not a law? I really liked your video, by the way. Great job!
Also, you seem to say Newton's laws are actual laws because there were other ways to measure it, like the electromagnetic force. But I think there weren't other ways to calculate force before Newton published his Principia. In that case, his equations only became actual laws (according to your definition) when other people came up with different ways to calculate dp/dt?
I find it hard to believe that someone could learn these concepts easier by not seeing these diagrams. I know there are people who fair easier with audial or tactile stimulation when it comes to learning (or so it seems.) Let's say we take any person with all their senses intact and present to them these concepts in only one way: audial, tactile, or visual. It's hard for me to believe that someone could better learn about these physical phenomena with audial or tactile information but no visual. I'm not even that visual myself. For instance, I listen to audiobooks a lot and most of the time, I don't paint a clear picture in my head about the stories or topics being presented (probably because I'm usually driving lol.) I can still understand what's being said and ponder upon it without visualization. Still, I find these visual presentations about physics to be far more helpful than just listening or just physically tinkering or rearranging. I know I'm being biased about this but I would like to hear the perspective of someone who, if they only had one form of stimulation to choose from, would learn better with some stimulation other than visual.
What's presented here is a simplified _model_ of the V I circuit relationship. You can write a more accurate model that takes account of the many other factors, but this version is good approximation for most DC circuits. Temperature co-efficients are easily accounted for but AC circuits, and RF circuits in particular, are where things get trickier.
Exactly. It would be like arguing the existence of Newton's Second Law, and the Law of Universal Gravitation. Both laws are generalities of a larger picture. For instance, the Law of Universal Gravitation works for smaller objects, but does not accurately calculate the orbit of Mercury.
Wow, very easy to understand these things explained things better than my instructors or teachers in college where they just read the books or what's inside the books in front without fully understanding the idea behide it and at the end we suffer. Thank you so much for making these kind of contents please continue doing
I think you missed the point of Ohm's law. The law doesn't say that the voltage divided by the current is the resistance. It states that: The current through a conductor between two points is directly proportional to the voltage across the two points. Now, the constant of proportionality is what we call the resistance. . In other words: Ohm's law states: V is directly proportional to I Definition of the resistance is R=V/I
Physics Videos by Eugene Khutoryansky This is already known.. Same as Hook's law (for example) is an approximation and is not applied in all cases to all elastic objects. But your misunderstanding of the law is in your interpretation of the law as merely the definition of resistance..It is not that: as I said above. So it is a "law" (limited .. I know !) and not a "definition" as you said in the video.
+Heliocentric I think the misunderstanding here about Ohm's law with respect to this video was that it is a physical principle or a concept that electromotive force (voltage in short no pun intended) pushes the current (which is the amperage) through a resistor or a device (resistance) across a circuit. It is not the formula E = IR nor the direct and inverse proportionality of the 3 physical entities/information.
The confusion lies in the conflation of 'resistor' and 'resistance'. V = I • R is indeed true regardless of the resistor used and the condition it is in. The R represents resistance, not resistor.
These animations are stunning! You make it easy to understand Ohm's Law. But personally, even at 2x speed, I find the video to be extremely slow. I guess that it makes these videos perfect for teachers in physics class, as they don't need to pause the animation during an explanation. Good work, keep it up :)
"Having more resistors is like having a smaller resistance." This choice of words illustrates exactly why I don't understand that splitting up the track increases the current.
Imagine being in a duel with swords. As long as the other person resists you sword attacks, you can't hit him. Hitting him really means getting through his blocking. If the other person resists your attacks as strongly as you attack, you won't be able to hit him. But when you do hit him, you hit him once at one time. In the above case, your opponent/resistance is really strong and you barely pass any hits. In another case, you have three weak opponents who are not strong, so you can hit them much easier than it is to hit a strong blocker. Similarly, the electricity that passes through three weak opponents (resistors) has an easier time getting through than the electricity that tries to get through a strong opponent (resistor).
@@excitedaboutlearning1639 The thing is, they're saying that 3 STRONG "opponents" is like having 1 WEAK "opponent". I think the trick is that you can "attack" them all at the same time but it's still counter-intuitive.
to have a meaningful existence a soul is like electron, it must pass many resistors and keep finding the return path even through the hardest resistance or jumping around various frequencies to make a complete journey in any given circuit (life time). That is the universal law.
I absolutely love these videos, they are beautiful in presentation whilst perfectly coupled with simplicity in explanation ...I wish I had access to this material as an Apprentice Electrician 30 years ago. It would have sped up my theory learning curve significantly. Amazing job....thank you
You really helped me a lot in my degree, I realy thank you, you doing a good job, I hope you make more videos especially in quantum mechanics and thermodynamics.
Original statement that Ohms law is NOT a law is at best MISLEADING and at worst plain WRONG! Ohms law established formula that Resistance R is proportional to the resistivity of the material (constant but different for given materials, such as copper, aluminum, gold, etc.) and the length of the wire and inversely proportional to the cross-section of the wire. That is the indeed the Law that Gerhard Ohm found. The reason why the resistance changes with temperature is precisely due to increase of the length of the wire with temperature increase resulting in proportional increase of the resistance. So, it is indeed a LAW even when you considered temperature effect! My daughter has made an experiment for sixth grade class of verifying Ohms Law by using different materials, like copper and aluminum wire and changing their length and measuring the current for a given DC voltage source to verify the above formula for Ohms Law. In fact, for magnetic circuits, Ohms law serves beautifully to introduce the equivalent dual concept, the Reluctance of the magnetic circuit as proportional to permittivity of the magnetic material, and the length of the magnetic core and inversely proportional to the cross section of the magnetic core. The AC inductance is then defined simply as turns squared times the reluctance! Dr. Slobodan Cuk (former Professor of Electrical Engineering at Caltech and inventor of Power Electronics switching converters). See my videos on RUclips.com/slobodancukTESLAco
The resistivity of a material is not constant, and that was my point. That is, even if you take the same length and width of the material, the total resistance may depend on temperature and a variety of other factors. It is just that for materials like aluminum and copper, this change is very small. But for the material used in thermistors, this change is very large, and this can't be explained in terms of the length or cross section of the material changing, but needs to be explained in terms of a change in the resistivity itself.
I understood the point about the controversy caused by the use of the word "law". Since my primary formation is as engineer, I am used to call it "Ohm's law", therefore in any mathematical relationship, a proportionality constant is used to fit the model to an "operational range". In this case, the R value is not really a constant that groups all the non-linear effects, moreover its definition only involves the V and I. For this reason, after the explanation of Eugene, I agree that it is not really a law, it is just a concept that works at a very basic level. Finally, it is importat to keep cuestionating all the knowledge, and also our own learning.
Ohms law can be stated for puplis more correctly for many devices as " the resistance of a metal device of constant temperature remains constant". And resistor can be defined " a device for which Ohms law is valid". In the transation to greek language I made sime small changes in terminology to make video "compatible" with greek educational school system and definitions.
V=I*R is not really Ohm's Law. V=I*R is how we define resistance, as you have clearly stated. A better formula for Ohm's law is dR/dV = 0 and dR/di = 0. Ohm's law is that resistance is not a function of electrical operating conditions. Given a resistor of a material that doesn't change identity or geometry, that is maintained at a particular temperature by an independent system, its ratio of voltage to current is the same no matter what the voltage or current is. That is what Ohm's law is.
Yes, thank you. Some straight answers for once. I don't know why there is all of this misinformation when learning things like this. I'll have to check out your other videos. Thanks again.
I summon thee Eugene of Physics Videos by Eugene Khutoryansky or anyone who can help :) what about defining Resistance in terms of resistivity , length and Area. Now one would say resistivity is self defined But no we can also relate it to fundamental physical quantities like mass of an electron , charge of an electron , relaxation time and number charge density(no. of electrons per unit volume). (further doubts) Isn't this the reason why Ohm's law specifically states that it's under constant temperature and physical conditions. And I LOVE your videos , IT FEELS SO GOOD VISUALIZING EVERYTHING , thanks so much for all your efforts.(TOO GOOD)
1. There are preconditions to this law such as 'under constant temperature' which is to imply that the law would be talking about a simplified model of real life system like most laws in physics. Therefore, it is to be used more as a guideline rather than as a law beyond textbooks. 2. The statement is also not R=V/R. Ohm's law statement is that current flowing (the effect) is proportional to voltage (the cause) across the resistor. Resistance is only the constant of proportionality to represent the law as an equality. Therefore, the law is not responsible for a variable resistance. Even under changing conditions (under the preconditions mentioned in 1), the law still holds.
Thank you for showing me way to magical science out of craming these not real laws which fails to understand this magical world of science and innovative thinking.
Sir, your videos are really helpful in getting a feel of the concept. Sir, could you please make videos on working of Diodes and Transistors. I am really struggling in understanding the working of these semiconductor devices.
Some comments and facts: When Ohm did this finding, there was no knowlege of electron or inside of atoms. Ohm found out that resistance is constant for metallic coductors, mainly copper, iron. He knew that resistance depends on temperature. There was not found yet the law of conservation of energy. Many other things were not known. We use nowadays resistance for example radiation resistance of dipoleantenna is 70 ohms. It's a feature of space, not any wireconductor. Explanation for electrons movement in conductor is quite complicated. It would be interesting to animate this properly.
I was not aware of the history. Thanks for the information. I will add the movement of electrons in conductors to my list of topics for future videos. Thanks.
You are right as this essentially is a DC circuit. The resistor upper terminal is positive and the lower one negative. Or the lecturer tried to draw the "counter vector" with same colour. In my ham radio training in the early 1980's the voltage drop was explained to be a counter vector of same size but opposite direction as the voltage measured accross the resistor. At that time they taught that the current flowing thru the load resistor gives rise to the voltage drop (counter vector) which has to be substracted from the battery voltage.
Ok so in any case anyone is still in the comments. Could someone clarify this for me? What this video is impling is that: "Ohm law does not define resistance outside of it, therefore it's not a law". In the principal example of Newton's second Law, that even without (F=M*a)acceleration could still be defined in some way. The reason of not being a law is that the Resistance does not have a *constant* for the actual resistance, since it would decreasse with temperature. So if in some way we define a constant for the *material* with the resistance at certain temperature; and another one for the *amount that it changes with temperature* and relate that through the current passing. Then it would be defined as a law? Like: *R = Constant - ValueOfChange*DiferenceInTemperature.* This way we could explain how the material change, and find a way to discover temperature by the new resistance. I mean this is what we did with most atomic numbers. Found the value for a constant and related that with somethin. Molar mass and avogrados.
The Feynmann lecture mentioned many times in the comments states that even the most fundamental laws are only approximations becouse reality never gets so simple as to be completly described by mathematical equations. On the other hand we have uncovered laws which are universal becouse they are approximations of some fundamentum underlying almost all physical phenomena. In my interpretation this video tells that there is no such fundamentum behind Ohms Law. For example as far as I know there is no universally valid the "R = Constant - ValueOfChange* DiferenceInTemperature" equation. If there is such a constant valid for at least all electro-conductive metallic material than perhaps Ohms law would indicate some fundamental quality of those materials. I have forgotten a lot about physics so maybe such a constant exists :)
Every engineer student should watch these videos or every instructor should show these videos to their students. Understanding these concepts by reading only is very difficult. Seeing it working like this is so much easier to understand.
A truly fantastic and novel way to educate the youth. When I was a youth I struggle to understand electric circuit theory; oh how I wish teaching material such as this channel were available!
so hold on. when the resistance changes as the resistor heats up, why does this change "ohms law" isnt that only changing one variable of the equation continuously, thereby changing the answer continuously? i dont know but doesnt it seem like ohms law is ever changing, along with the resistance?
Hence why the its Voltage/Current = Resistance and not Voltage/Current = Original resistor value. the clue is in the name, if the resistance alternates, more current flows, and the increase in current flow across it is proportional to the resistors deterioration. Therefore the law still applies :D
Johannes Sjolte I thought the same, but there is one difference. Both laws share the fact that you can define a new physical parameter, mass or resistance. But in Ohm's Law you have some materials that doesn't obey it, while in the other case every object has its mass remaining constant. But, that never happens actually, because of Special Relativity… Therefore… Ohm's Law is fine, but has that particularity which other laws doesn't have.
My high school teacher told us to think of resistance intuitively as of the amount of collisions that the electrons experience as they go through the wire, for example.: resistance increases with temperature because the atoms in the wire (or within the resistors) are vibrating more and thus are more likely to impede the path of the electrons; also the longer the resistor or the smaller its cross-sectional area, the more collisions. Is there any way to relate this approach to the existing definition of resistance as voltage/current ?
I have read somewhere that electric "flow" is dependent on the surface of the conductor and electricity spreads due to changes in the magnetic field surrounding the wire....
That's the reason why current is same in series circuit. The Resistors reduce the voltage and so, as I=V/R, so reduced voltage will automatically result in reduced current! As less potential difference will cause lesser attraction and slow the current down.
Наука
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Ok?
I guess this is quality content. Thanks for the info on subtitles but I already knew it
@@JjMn1000 how dare you to say ' I guess'. It is quality content
Thank you Eugene 👍👍👍
Are you using Manim or using other softwares?
Nice work. Thank you. New generation is very lucky. When I was an engineering student (30 years ago) we had only paper, pencil, books and blackboard. These kind of videos should be considered as a big revolution in education.
Thanks.
Yeah, I remembered how much trouble I did when I was 14 years old (in 1993) trying to have a comprehension of all those electrical phenomenon that are very easy to understand using animations nowadays.
i thought it was 40 years ago?
Yes sir
I agree that this videos are astonishing useful and beautiful. However, there're evidence (my apologies for not find the source; I explain it below) that images associated with text are as good as animations, if not superior. This phenomenon is related with "brain effort" to learn the schema, concept or principle.
I remember Derek Muller (Veritasium) discuss it in one of his videos, but as I search through his channel, I couldn'r find it. It is in one of his videos about education and learning.
Edit: found it --> ruclips.net/video/GEmuEWjHr5c/видео.html
Now I finally understood why resistors in parallel gives less recistance.
Glad I was able to help.
Xremote. Please don't do it. You'll ruin the understanding of what is electricity forever.
Except water flowing in pipes is usually a non-linear relationship between flow rate and pressure drop, so it is more difficult to make the analogy mathematically accurate.
carultch. Not only that. The electric phenomena is tridimensional, happens in the space around the circuit. At any given instant half of the energy is in the space and half in the circuit. Actually the energy is flowing from the battery to the space and from the space to the conductor. The Voltage, the electric force, is not like a pressure pushing the electrons, the Voltage is a field in the space. The magnetic field is not a waste product of the electrons movement, magnetic field stores energy in the space! The energy is flowing from the space to the wire perpendicularly.
That's quite important... A lot of people use pipes to make analogy for electricity, which seems to be extremely convenient at first, but I think that now I understand why I wasn't able to grasp the concepts of electricity fully... Thanks!
I recently created a Patreon account for people who want to help support my channel. The link is on my RUclips home page and in the video description up above. Also, in case, you have not already seen them, I uploaded several other videos recently. As always, for each video that you like, you can help more people find it in their RUclips search engine by clicking the like button, and writing a comment. Lots more videos are coming very soon. Thanks.
+Eugene Khutoryansky These are such amazingly high quality videos. I'm shocked at how many high quality, illustrative videos you have on your channel. I'll see if I can donate a bit to your patreon account :). Keep up the awesome work. Mathematics and sciences are, in my humble opinion, the most beautiful and fulfilling study that one can engage in. Thanks for making it accessible to the massive amount of scientifically illiterate people.
+Chris Johnston, thanks for that really great compliment about my videos, and I really appreciate the donation. Thanks.
+Eugene Khutoryansky I don't know what a patreon account is; but your videos have always been amazing and I think it's well worth donating a few bucks for all the value I get out of your channel.
+Physics Videos by Eugene Khutoryansky Your videos on electric circuits are awesome. I use them on a regular basis and my students love them. They really help to re-enforce what the text book is saying. Is it possible to make a video on Alternating Current and Alternating Current Circuits. The future Aircraft Technicians would greatly appreciate this.
+Physics Videos by Eugene Khutoryansky All the equations for physics are dependant to physical parameters. The viscosity, thermal conductivity, electrical conductivity and speed of light depend on the medium. Thus, ohm's law is correct, but one must apply differential form of equation to solve complex problems, not simplified form that is constant parameter solution of ohm's differential law.
OMG! I've been studying all this stuff on my own and when I started investigating concepts around Resistance I came to a similar idea about the fallacy but couldn't articulate it since I didn't know enough. I'm so greatful that this video goes into it because I thought I was crazy lol!
Thanks. I am glad you liked my video.
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Thanks.
Resistance is futile!
Like your life
@@adrians.4311 like every-body`s life... :)
Hey, thats MY line!
Ohms law also states .....provided that the temp remains constant
Exactly, even the voltage varies with the variation of the external resistance, due to the internal resistance of the real generator, the ohm law must be interpreted assuming the ideal case, the real case can always be traced to the summation of the ideal cases. Ohm's law is essential for calculating the circuit because it is very close to the ideal case.
I really thank you. Your video is a simple and clear illustration of how voltage, resistance and current intensity interact. One can watch it OBSERVE, SEE how it works clearly. You are helping lots of people to really understand the basics of electricity. Thank you.
My momma always said, "Life is like a box of resistors. You never know what you're gonna get."
Maybe she should've learned how to read resistor color codes.
"There are many examples in logic where a statement is always true simply because of the way in which we created our definitions for the words, and the statement doesn't actually tell us anything about the external world around us.This one of the logical fallacies we need to watch out for, both with regards to science and also with regards to life in general."
Boom.
can YOU please elaborate? THANKS.
@@naveensundar4765 Let's look at the statement that immediately precedes that one:
"The fact that the number that we get at any given time is always equal to the resistance of the material is simply due to the fact that this is how we defined the word 'Resistance' in the first place."
Let's say we had workers packing apples in a factory. We can create a value for each worker called "productivity" (P), which is the number of apples (A) they packed in a given period of time, divided by the number of hours that they worked (T).
P = A / T
A worker whose productivity is 500 can pack 500 apples in one hour (seems pretty slow, but we'll ignore that).
Next, we make an observation: if we know a worker's productivity (P), then we can predict how many apples (A) they can pack in a given amount of time (T).
A = PT
This is a valid observation, however we haven't actually learned anything. P was already derived from A and T, so deriving A from P and T doesn't tell us anything new about the nature of our factory. At best, in this exercise we have learned about the multiplication property of equality, which allowed us to re-arrange the factors to solve for a different variables. In which case, we've learned something new about math, but not about apples, time, or productivity.
I believe Khutoryansky was referring to circular logic. For example, a society might decide that drinking alcohol is immoral, so they make a law against it. Now it is illegal. It is illegal because it is immoral. Now, imagine someone new enters the society, and they discuss alcohol with some of the locals.
"If you like to drink alcohol, we will not accept you as a friend. Drinking alcohol is wrong."
"Why is it wrong?"
"Because it is illegal. Only an immoral person would want to do something that is illegal."
Then it isn't a discussion about alcohol at all. They are simply deriving immorality from illegality, when illegality was originally derived from immorality. This is a closed loop, where no new information is allowed out or in. In fact, we can't trace the origin of the "immorality" label for alcohol. How did it come to be immoral in the first place? "The Law of the Immorality of Alcohol", then, isn't a new law in the scientific sense. It's just a logical derivation of the previous "The Law of the Illegality of Alcohol".
I believe this was the intended point. Not specifically about alcohol, of course.
@@tom_something Thanks.MIND=BLOWN
@@tom_something What about the equation for force then? Consider a mass, M, falling near earth's surface at acceleration g. We define force: F=Mg. But what if we did not actually know g, for whatever reason, and we knew M and F, then we could 'learn something new about the world' by finding g from g=F/M. But... Do we really learn something about the external world or just a construct of ours? We like to think of a force as a property of the physical world but that is ultimately based on acceleration and mass, and acceleration is based on time and velocity, which is based on position. The only 'tangible' things here are perhaps position, mass, and time. Does this make velocity, acceleration, and force a construct that is just as invented as resistance?
@@Nelson-sr2bi Yes, in fact.
Something that would qualify as an actual law of physics would be, say, the Law of Conservation of Momentum, or the Law of Conservation of Energy. Neither of those laws are derivable from our definitions of momentum or energy (p = mv or e = 1/2mv^2 as an example), or are they definitions of some other variable. Those laws genuinely tell us something about the universe, which is what separates them from simple definitions like F=ma.
By the way, just because we chose to define things like velocity and acceleration doesn't mean that they aren't real. After all, the laws I mentioned actually rely on our definitions of mass and velocity to be meaningful.
Thank you very much, your lessons makes things so crystal clear replacing memorization with real, deep understanding.
This is a very impressive animation that actually clear the doubts and expose the actual practical concept behind. Thank you for making such videos.
The mentioned fallacy states that a law which has been formulated is a mathematical representation for a model that describes something observable in the real world. That one model works together with all the other models may seem like a coincidental happenstance to critics of science, but it actually is a beautiful hint that the 'laws' are just implications of higher abstractions.
Some people say scientists act like there is only one truth and they know it. Maybe some scientists are that way. But the truth is, scientists just state that their model works and fits in the picture.
I just watch half the video and this channel is one of my favorits now
+netauri123, that's great to hear. Thanks. I am glad to be one of your favorite channels.
You are helping millions of students around the world..........................................never stop
When showing a higher or lower value of resistor may be better by lengthening or shortening rather than make the resistor a smaller diameter for a smaller resistance; because typically a smaller diameter resistor does not indicate less resistance but more resistance.
I also agree with a previous comment of "but that doesn't mean that the voltage drop across a ckt element is not proportional to the current flowing through it "
Thank you for your animation and will looking for to an update.
You would have to chnge the simulated visual representation from a cricked line into
a tunnel. I find the line repr. very useful.
Not only are these videos perfect visual presentations, but the final thoughts of this particular video was almost existential. :)
Love your work, thanks.
Thanks.
Ohm's observation was that the apparent Potential drop across an ideal Resistor is proportional to the Current through it. So, V=RI would be the linear model accounting for V versus I data. Yet, one uses I-V characteristics, which gradient equals 1/R (conductance). This tells us how fast the charge transport can be through the Resistor.
Hence, Resistance is a measure of the charge transport time!
*R ~ t*
Yet, in a real _ohmic_ resistor, temperature might increase with time, so the I-V slope changes, depending on the experimental procedure...
Came for Ohms law, left with a life lesson
Eugene, the way you create your videos is genius. I always enjoy watching them.
Thanks.
these videos are so coincidental because I just started my circuits class and it's like you make videos following the progression of my class :)
+Blackyisacat, I am glad that these videos are getting to you in time. In the past, I had a person complain that the video was on a topic that he had just taken his final exam in, and that if the video had been released just a few days earlier, it would have helped him correctly answer the question that he missed.
It only appears coincidental. Google knows everything. :-)
@@flumpyhumpy even till today
MAF sensors in cars use this property of resistors to measure the volume of air passing through it. Excellent video. Keep up the good work!
Finally I came to know about Resistor ! Thanks for the video !
Thank you! I have been trying to make sense of this for years. A little closer. Love the ending.
Thanks.
Feeling fortunate enough to find such quality content on electrical engineering
I'm using these videos in my class, these videos are helping my students a lot.
The video was great and the music was stimulating. Thanks for sharing. I'm definitely gaining confidence in this subject. I appreciate it!
Thanks. Glad you liked my video.
Your channel is great source to understand difficult concepts by esay way. Please make electrical machine related videos.
Ive spent hours upon hours trying to understand resistance and get an intuiative feel about how it worked and this video is the only one that got me to figure it out.
I am glad my video was helpful.
These videos are so good. I wish I had known about them when I was in Physics II a few years ago.
Totally love your videos, they take something that may seem so abstract at first and turns it into a concrete and visual explanation that is incredibly helpful when studying physics. Thanks again!
Thanks. I am glad you like my videos.
Hi Eugene, during my studies in high school I would have needed these kind of representations of how electicity works.
Now, all thank to you, I can put images and representations on what I know of electricity, and it makes way more sense
+Pierre Leblanc, I am glad to hear that my videos helps make this subject make more sense. Thanks.
Excellent video and very clear explanation, thank you so much!
i have multiple accounts, and multiple times i would find your videos for mutiple reason. And, in all of those scenarios, i would like, subscribe and thank you. So here i am again: Thank you.
In programming, this would be called a leaky abstraction. It's an analogy that works most of the time, but "leaks" under certain circumstances.
Thank you! Thank you! Thank you! This has been driving me nuts for days, but now I get it. Absolutely brilliant animations! ❤️💡❤️
Thanks. I am glad you liked my video.
Khutoryansky's definition: "Physical laws tell us how the Universe works." ( 3:27 )
Ohm's Law tells us that the resistance of an object at a certain time is equal to the voltage across the object at that time divided by the current through the object at that time.
Because of Ohm's Law, if you know two of the three values (1. Resistance 2. Voltage 3. Current) for a certain object at a certain time, then you can calculate the third value of the object at that time. It is possible to calculate and consequently know the third value because Ohm's Law tells us how the three values work in the Universe.
Ohm's Law tells us how a part of the Universe works, and thus is a law by Khutoryansky's definition of a physical law. The Universe works in way that when the resistance of an object changes (whether by temperature or some other change in the object), current through the object changes because the voltage across the object remains the same. Ohm's Law tells us about this way that the Universe works.
"the statement doesn't actually tell us anything about the external world around us." ( 5:29 )
The statement of Ohm's Law tells us how the resistance of an object, the voltage across the object, and the current through the object are related, like how the equation F = ma (Newton's Second Law) tells us how the force applied to an object will relate to the mass of the object and the acceleration of the object caused by that force.
"There are many examples in logic where a statement is always true simply because of the way in which we created our definitions for the words, and the statement doesn't actually tell us anything about the external world around us." ( 5:19 )
F = ma is always true because we have defined force as a thing measured in joules where 1 joule = 1 kg * 1 m/s^2, so of course X joules will equal Y kg * Z m/s^2.
My first two paragraphs apply the same way to Newton's Second Law. Read them with the terms replaced:
[Newton's Second Law] tells us that the [force applied to an object] is equal to the [mass of the object] [multiplied] by the [acceleration of the object caused by that force].
Because of [Newton's Second Law], if you know two of the three values (1. [Force] 2. [Mass] 3. [Acceleration]) for a certain object at a certain time, then you can calculate the third value of the object at that time. It is possible to calculate and consequently know the third value because [Newton's Second Law] tells us how the three values work in the Universe.
If I am missing something, please explain. I will try my best to understand.
+Blake Callahan, in the case of F = mA, force is defined independently of this equation. For example, we have laws for how forces on charged particles are generated as the result of electric and magnetic fields. On the other hand, in the case of R=V/I, resistance is defined entirely by this equation. F=mA relates how something which already has a definition (force) relates to other observable quantities. On the other hand, R=V/I does nothing other than to just create a definition for the quantity "V/I".
+Eugene Khutoryansky What is the definition of force independent of F = ma?
+Blake Callahan, in the case of an electromagnetic force, we have F = q[E + v x B].
This is just one example, as other types of forces have other equations.
+Eugene Khutoryansky I'm not sure I understand your logic regarding what makes a law. Newton tells us force is the time derivative of momentum. That's true, according to him. Then, we find other ways to calculate force, as you pointed out in your comment. But wouldn't it just be another way to calculate the time derivative of momentum?
If you say Ohm's law is not a law because resistance is only a way to define V/I, wouldn't force just be another way to define dp/dt, thus making it not a law?
I really liked your video, by the way. Great job!
Also, you seem to say Newton's laws are actual laws because there were other ways to measure it, like the electromagnetic force. But I think there weren't other ways to calculate force before Newton published his Principia. In that case, his equations only became actual laws (according to your definition) when other people came up with different ways to calculate dp/dt?
This is for the visual learners lol
I find it hard to believe that someone could learn these concepts easier by not seeing these diagrams. I know there are people who fair easier with audial or tactile stimulation when it comes to learning (or so it seems.) Let's say we take any person with all their senses intact and present to them these concepts in only one way: audial, tactile, or visual. It's hard for me to believe that someone could better learn about these physical phenomena with audial or tactile information but no visual. I'm not even that visual myself.
For instance, I listen to audiobooks a lot and most of the time, I don't paint a clear picture in my head about the stories or topics being presented (probably because I'm usually driving lol.) I can still understand what's being said and ponder upon it without visualization. Still, I find these visual presentations about physics to be far more helpful than just listening or just physically tinkering or rearranging.
I know I'm being biased about this but I would like to hear the perspective of someone who, if they only had one form of stimulation to choose from, would learn better with some stimulation other than visual.
Its more attractive tho
are you blind
I am just learning electricity new new.
so I don’t understand why to use resistors.???
What's presented here is a simplified _model_ of the V I circuit relationship. You can write a more accurate model that takes account of the many other factors, but this version is good approximation for most DC circuits. Temperature co-efficients are easily accounted for but AC circuits, and RF circuits in particular, are where things get trickier.
Exactly. It would be like arguing the existence of Newton's Second Law, and the Law of Universal Gravitation. Both laws are generalities of a larger picture. For instance, the Law of Universal Gravitation works for smaller objects, but does not accurately calculate the orbit of Mercury.
this was truely amazing :) thank you again for a lovely video.
+Men Skills, thanks for the compliment. I am glad you liked my video.
Wow, very easy to understand these things explained things better than my instructors or teachers in college where they just read the books or what's inside the books in front without fully understanding the idea behide it and at the end we suffer. Thank you so much for making these kind of contents please continue doing
Thanks for the compliment about my videos.
I think you missed the point of Ohm's law.
The law doesn't say that the voltage divided by the current is the
resistance.
It states that: The current through a conductor between two points is
directly proportional to the voltage across the two points.
Now, the constant of proportionality is what we call the resistance.
.
In other words: Ohm's law states: V is directly proportional to I
Definition of the resistance is R=V/I
+Heliocentric I'd like to know what Eugene thinks about this, since what you say seems true.
+Heliocentric, but the current is not necessarily directly proportional to the voltage, and that was my point.
Physics Videos by Eugene Khutoryansky
This is already known.. Same as Hook's law (for example) is an approximation and is not applied in all cases to all elastic objects.
But your misunderstanding of the law is in your interpretation of the law as merely the definition of resistance..It is not that: as I said above.
So it is a "law" (limited .. I know !) and not a "definition" as you said in the video.
+Heliocentric I think the misunderstanding here about Ohm's law with respect to this video was that it is a physical principle or a concept that electromotive force (voltage in short no pun intended) pushes the current (which is the amperage) through a resistor or a device (resistance) across a circuit.
It is not the formula E = IR nor the direct and inverse proportionality of the 3 physical entities/information.
The confusion lies in the conflation of 'resistor' and 'resistance'. V = I • R is indeed true regardless of the resistor used and the condition it is in. The R represents resistance, not resistor.
These animations are stunning! You make it easy to understand Ohm's Law. But personally, even at 2x speed, I find the video to be extremely slow. I guess that it makes these videos perfect for teachers in physics class, as they don't need to pause the animation during an explanation. Good work, keep it up :)
+Gabriel Cossette, thanks.
This video is worth thousand textbook pages. Also it is very enjoyable. I take my hat off to you.
Thanks. I am glad you liked my video.
"Having more resistors is like having a smaller resistance."
This choice of words illustrates exactly why I don't understand that splitting up the track increases the current.
Imagine being in a duel with swords. As long as the other person resists you sword attacks, you can't hit him. Hitting him really means getting through his blocking.
If the other person resists your attacks as strongly as you attack, you won't be able to hit him. But when you do hit him, you hit him once at one time.
In the above case, your opponent/resistance is really strong and you barely pass any hits.
In another case, you have three weak opponents who are not strong, so you can hit them much easier than it is to hit a strong blocker.
Similarly, the electricity that passes through three weak opponents (resistors) has an easier time getting through than the electricity that tries to get through a strong opponent (resistor).
@@excitedaboutlearning1639 The thing is, they're saying that 3 STRONG "opponents" is like having 1 WEAK "opponent".
I think the trick is that you can "attack" them all at the same time but it's still counter-intuitive.
Everyone should thoroughly understand this tutorial before going any further.
A thank you.
Thanks.
These transitions are blowing my mind.
I FINALLY GET IT WHY YOU NEED TO SUM ALL THE VOLATGE CREATED BY THE RESISTORS WHILE STACKED IN SERIES .
THANK YOU SO MUCHH
Glad my video was helpful. Thanks.
Thank you for the subtitles.
What a beauty! You seamlessly intertwined Life philosophy with Science at the end. You are THE BEST!😊
Thanks.
to have a meaningful existence a soul is like electron, it must pass many resistors and keep finding the return path even through the hardest resistance or jumping around various frequencies to make a complete journey in any given circuit (life time). That is the universal law.
I absolutely love these videos, they are beautiful in presentation whilst perfectly coupled with simplicity in explanation ...I wish I had access to this material as an Apprentice Electrician 30 years ago. It would have sped up my theory learning curve significantly.
Amazing job....thank you
Thanks for the compliment about my videos.
fantastic video and great animation. Thank you for sharing.
Well said, "both with regards to science, and also with regards to life in general".
You really helped me a lot in my degree, I realy thank you, you doing a good job, I hope you make more videos especially in quantum mechanics and thermodynamics.
Thanks. I am glad my videos are helpful. More videos are on the way.
Great explanations and fantastic animations! Superb music, also!
Thanks for the compliments.
Great video, as always!! Thank you!
+Theenerd ジェームズ, Thanks. I am glad that you liked this one too.
Original statement that Ohms law is NOT a law is at best MISLEADING and at worst plain WRONG! Ohms law established formula that Resistance R is proportional to the resistivity of the material (constant but different for given materials, such as copper, aluminum, gold, etc.) and the length of the wire and inversely proportional to the cross-section of the wire. That is the indeed the Law that Gerhard Ohm found. The reason why the resistance changes with temperature is precisely due to increase of the length of the wire with temperature increase resulting in proportional increase of the resistance. So, it is indeed a LAW even when you considered temperature effect! My daughter has made an experiment for sixth grade class of verifying Ohms Law by using different materials, like copper and aluminum wire and changing their length and measuring the current for a given DC voltage source to verify the above formula for Ohms Law. In fact, for magnetic circuits, Ohms law serves beautifully to introduce the equivalent dual concept, the Reluctance of the magnetic circuit as proportional to permittivity of the magnetic material, and the length of the magnetic core and inversely proportional to the cross section of the magnetic core. The AC inductance is then defined simply as turns squared times the reluctance! Dr. Slobodan Cuk (former Professor of Electrical Engineering at Caltech and inventor of Power Electronics switching converters).
See my videos on RUclips.com/slobodancukTESLAco
The resistivity of a material is not constant, and that was my point. That is, even if you take the same length and width of the material, the total resistance may depend on temperature and a variety of other factors. It is just that for materials like aluminum and copper, this change is very small. But for the material used in thermistors, this change is very large, and this can't be explained in terms of the length or cross section of the material changing, but needs to be explained in terms of a change in the resistivity itself.
I understood the point about the controversy caused by the use of the word "law". Since my primary formation is as engineer, I am used to call it "Ohm's law", therefore in any mathematical relationship, a proportionality constant is used to fit the model to an "operational range". In this case, the R value is not really a constant that groups all the non-linear effects, moreover its definition only involves the V and I. For this reason, after the explanation of Eugene, I agree that it is not really a law, it is just a concept that works at a very basic level. Finally, it is importat to keep cuestionating all the knowledge, and also our own learning.
Amazing! wish this was how it was explained to us in school :(
superb.. ..visulalizaton is ultimate.... Thq Eugene Khutoryansk.. really interesting
+avinash nani, Glad you liked it. Thanks.
Ohms law can be stated for puplis more correctly for many devices as " the resistance of a metal device of constant temperature remains constant". And resistor can be defined " a device for which Ohms law is valid". In the transation to greek language I made sime small changes in terminology to make video "compatible" with greek educational school system and definitions.
V=I*R is not really Ohm's Law. V=I*R is how we define resistance, as you have clearly stated. A better formula for Ohm's law is dR/dV = 0 and dR/di = 0.
Ohm's law is that resistance is not a function of electrical operating conditions. Given a resistor of a material that doesn't change identity or geometry, that is maintained at a particular temperature by an independent system, its ratio of voltage to current is the same no matter what the voltage or current is. That is what Ohm's law is.
thank you very much .you r my virtual best teacher
Yes, thank you. Some straight answers for once. I don't know why there is all of this misinformation when learning things like this. I'll have to check out your other videos. Thanks again.
Thanks.
I summon thee Eugene of Physics Videos by Eugene Khutoryansky or anyone who can help :)
what about defining Resistance in terms of resistivity , length and Area. Now one would say resistivity is self defined But no we can also relate it to fundamental physical quantities like mass of an electron , charge of an electron , relaxation time and number charge density(no. of electrons per unit volume).
(further doubts) Isn't this the reason why Ohm's law specifically states that it's under constant temperature and physical conditions.
And I LOVE your videos , IT FEELS SO GOOD VISUALIZING EVERYTHING , thanks so much for all your efforts.(TOO GOOD)
I really needed this. Thx a lot for this amazing video ❤️✨
Thanks. I am glad you liked my video.
Wow! Electricity, Physics and Philosophy in one lesson! Good series.
Thanks.
Hmm... I never though about that, Thanks, your videos are descriptive.
It's really amazing. .thanks eugene ☺☺
I would love to see you do some stuff on RF through Coax from an electrical perspective
1. There are preconditions to this law such as 'under constant temperature' which is to imply that the law would be talking about a simplified model of real life system like most laws in physics. Therefore, it is to be used more as a guideline rather than as a law beyond textbooks.
2. The statement is also not R=V/R. Ohm's law statement is that current flowing (the effect) is proportional to voltage (the cause) across the resistor. Resistance is only the constant of proportionality to represent the law as an equality.
Therefore, the law is not responsible for a variable resistance. Even under changing conditions (under the preconditions mentioned in 1), the law still holds.
Thank you for showing me way to magical science out of craming these not real laws which fails to understand this magical world of science and innovative thinking.
Casually watching some science stuff when at the end, it suddenly becomes a life lession... :|
I like your videos because it very difficult to visualise it ,now it is very easy and clear
Plz try to make physics videos in all topics of class 10
Sir, your videos are really helpful in getting a feel of the concept. Sir, could you please make videos on working of Diodes and Transistors. I am really struggling in understanding the working of these semiconductor devices.
what a beautiful combination of Beethoven and physics
Thank you so much for your help
Liked it, why do I learn more from you than my teachers?? Lol
Douglas Chen don't learn from school if it's above primary/elementary level
Kira Vincent-Davis 😄
She's incredibly articulate, she does Anime voices also
School isnt effective at it's job, and it's job isnt desirable in the first place
love these videos .....
Some comments and facts: When Ohm did this finding, there was no knowlege of electron or inside of atoms. Ohm found out that resistance is constant for metallic coductors, mainly copper, iron. He knew that resistance depends on temperature. There was not found yet the law of conservation of energy. Many other things were not known. We use nowadays resistance for example radiation resistance of dipoleantenna is 70 ohms. It's a feature of space, not any wireconductor. Explanation for electrons movement in conductor is quite complicated. It would be interesting to animate this properly.
I was not aware of the history. Thanks for the information. I will add the movement of electrons in conductors to my list of topics for future videos. Thanks.
This is so fucking enlightening... thank you!
Great tutorials, thanks for showing
At 3:15 I suggest the pink arrow of the voltage of the resistor to be pointing down only to indicate that it's voltage drop
You are right as this essentially is a DC circuit. The resistor upper terminal is positive and the lower one negative. Or the lecturer tried to draw the "counter vector" with same colour. In my ham radio training in the early 1980's the voltage drop was explained to be a counter vector of same size but opposite direction as the voltage measured accross the resistor. At that time they taught that the current flowing thru the load resistor gives rise to the voltage drop (counter vector) which has to be substracted from the battery voltage.
Perfect ending!! Clap clap clap!!
Thank you Eugene.
+XtroTheArctic, thanks for the compliment about the ending. Glad you liked it.
Same! (Y)
Ok so in any case anyone is still in the comments. Could someone clarify this for me?
What this video is impling is that: "Ohm law does not define resistance outside of it, therefore it's not a law". In the principal example of Newton's second Law, that even without (F=M*a)acceleration could still be defined in some way. The reason of not being a law is that the Resistance does not have a *constant* for the actual resistance, since it would decreasse with temperature.
So if in some way we define a constant for the *material* with the resistance at certain temperature; and another one for the *amount that it changes with temperature* and relate that through the current passing. Then it would be defined as a law? Like: *R = Constant - ValueOfChange*DiferenceInTemperature.* This way we could explain how the material change, and find a way to discover temperature by the new resistance.
I mean this is what we did with most atomic numbers. Found the value for a constant and related that with somethin. Molar mass and avogrados.
The Feynmann lecture mentioned many times in the comments states that even the most fundamental laws are only approximations becouse reality never gets so simple as to be completly described by mathematical equations. On the other hand we have uncovered laws which are universal becouse they are approximations of some fundamentum underlying almost all physical phenomena. In my interpretation this video tells that there is no such fundamentum behind Ohms Law. For example as far as I know there is no universally valid the "R = Constant - ValueOfChange* DiferenceInTemperature" equation. If there is such a constant valid for at least all electro-conductive metallic material than perhaps Ohms law would indicate some fundamental quality of those materials. I have forgotten a lot about physics so maybe such a constant exists :)
Wonderful job, thanks you so much
Every engineer student should watch these videos or every instructor should show these videos to their students. Understanding these concepts by reading only is very difficult. Seeing it working like this is so much easier to understand.
A truly fantastic and novel way to educate the youth. When I was a youth I struggle to understand electric circuit theory; oh how I wish teaching material such as this channel were available!
+Henderson Hood, thanks for the compliment.
Many people think that V=IR is Ohm's law, but this equation is not Ohm's law. It's just the equation that defines "electrical resistance".
so hold on. when the resistance changes as the resistor heats up, why does this change "ohms law" isnt that only changing one variable of the equation continuously, thereby changing the answer continuously? i dont know but doesnt it seem like ohms law is ever changing, along with the resistance?
Hence why the its Voltage/Current = Resistance and not Voltage/Current = Original resistor value. the clue is in the name, if the resistance alternates, more current flows, and the increase in current flow across it is proportional to the resistors deterioration. Therefore the law still applies :D
Go ahead dears.I have learnt many new idea of current laws.May allah bless you.Carry on.
Thanks for creating such an animation vedios.
Glad my video was helpful. Thanks.
Your videos are the best!
Thanks for the compliment.
It is a law. It's a law that tell us that current directly proportional to the voltage.
Johannes Sjolte Not an universal law.
Neither is Newton’s 2. Law
Johannes Sjolte I thought the same, but there is one difference. Both laws share the fact that you can define a new physical parameter, mass or resistance. But in Ohm's Law you have some materials that doesn't obey it, while in the other case every object has its mass remaining constant. But, that never happens actually, because of Special Relativity…
Therefore… Ohm's Law is fine, but has that particularity which other laws doesn't have.
This channel is superb
Thanks.
Thanks again for your help
Did i just a video where Eugene and the Narrator roasted Ohms Law
Nice and clear explanation.... Thank you
Thanks.
My high school teacher told us to think of resistance intuitively as of the amount of collisions that the electrons experience as they go through the wire, for example.: resistance increases with temperature because the atoms in the wire (or within the resistors) are vibrating more and thus are more likely to impede the path of the electrons; also the longer the resistor or the smaller its cross-sectional area, the more collisions. Is there any way to relate this approach to the existing definition of resistance as voltage/current ?
I have read somewhere that electric "flow" is dependent on the surface of the conductor and electricity spreads due to changes in the magnetic field surrounding the wire....
Thanks for the video! You obviously know a great deal so we must ask you why, oh why, the intrusive music? Best of luck!
Yeah it really didn't belong in a science video of this type. Otherwise it's a good video.
That's the reason why current is same in series circuit. The Resistors reduce the voltage and so, as I=V/R, so reduced voltage will automatically result in reduced current! As less potential difference will cause lesser attraction and slow the current down.