The same question I had when I was in 10th grade in 2013 and I and one my friend asked the teacher when he was doing derivation of series resistance connection we asked why the current is same after passing R1, R2 and R3 resistance. "Current kam kyo nahi hui"he said" kam hoti hai lekin bahut thodi isiliye " I knew he didnt know and after a month I guess, I had understood that by myself and let my friend know about that and we both were happy and satisfied. Agar abhi kisi ko samajh nahi aaya mtlb agar resistane add krte hai toh decrease pure circuit me hoti hai lekin pure circuit me same rahti hai.
lol in my case as also my physics teacher couldn't answer but she got impressed by it. She was at least a good person without ego and acknowledged her limits. School teachers often teach 2-3 subjects, at least when I was in school, not easy to go in depth.
My father was also an associate professor of Physics, he used to explain me exactly like this during my school and university days... flow of current is like flow of water in pipe and voltage is like how high your tank is, Higher the height of tank/voltage faster the water/current flow. Miss you dad. 😔
@@pranjulunrecognized not continuity equation,sir has considered two different pipes ,do you get it? So a1v1=a2v2 doesnt explain anything in this context,its all about more the area of pipe,less is the resistance offered to water flow thus more is the speed this analogy has nothing to do with equation of continuity
Same example my dad gave me when I was in 10th. Proud of him coz of his knowledge. No teacher in school or college told me this and now directly by Sir HC Verma
i wish when i was in 11th in 2003 the youtube having such videos and we should not pay 40rs /hour for internet cafe with very slow speed . what i remember is yahoo messenger with ASL Plz (Age Sex and Locaction)
Sir, Some points are missing in the explanation, i.e. The volume of charge will remain same not the speed (velocity) in one second. The velocity of the electron (water in analogy) doesn't matter, the most important thing is the volume of charge (electrons) passing through the wire cross-section per second. I just have uploaded a better explanation. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-KP2UMpjsYGs.html
@@Unknown-ei1eg Prof Verma already explained that the current doesn't get reduced.. Because current is nothing but flow of charge.. The movement of charge is slowed down by resistor but it doesn't block any of the charge..
@@jdgoel4817 (I’m not professionally trained with electronics so this might be very wrong, it’s how I currently view this). Keeping this analogy going; whenever you bump into someone or something you convert your movement into heat. You then start walking again, because you aren’t where you want to be and there is space somewhere else that just opened up. This doesn’t change that the amount of people going into the crowded place is always the same as the amount of people going out. As for where the energy for the heat comes from, that is from the pressure pushing the people in and the pressure pulling the people out. Because the person lost their kinetic energy bumping into something, it must (in a sense) “consume” some of the pressure to get moving again. Pressure is similar to the voltage difference between two places.
In our education system, textbooks of lower standards creates confusion in view of teaching the students in a easy way ,but when at higher level we get to know the reality we are not even concerned to accept it, I thinks these types of misconception should be sorted at the first time to not crate any mess further
I am surly agreed with your answer sir, sorry But then what will be the use of resistor ? What difference it will make in using it and not using it in a circuit ?
NOPE , BASICALLY RESISTOR IS A METAL AND METAL HAS SOME ELECTRONS IN IT , SO WHEN A BATTERY IS CONNECTED TO A RESISTOR IT CREATES POTENTIAL DIFFERENCE ACROSS THE RESISTOR AS A RESLUT ELECTRONS WHICH ARE NEGATIVELY CHARGED GET ATTRACTED TO POSITIVE TERMINAL OF BATTERY AND START MOVING TOWARDS THE + TERMINAL AND THIS MOVEMENT OF ELECTRONS RESULTS CURRENT
@@masad7315 if democracy is allowed just like flow of charge in conductor and islam provide low resistance then only physics will survive in pakistan or else maulana will destroy ur country
Those Who have DISLIKED This Video have no Idea that he is our Honourable Legendary physics Prof HC Verma . Almost all physics students have gone through his books .
This is an excellent question from anyone starting their electrical study. Across an ideal resistor, Voltage reduces/drops in the direction of current flow - but the current remains the same. This is the basis of KCL/KVL which you must understand to do any circuit analysis. My analogy will also use water through a pipe. The pressure on one end (voltage) forces water (charge) to flow (current) through the pipe. If you squeeze the pipe (resistance) in the middle, the pressure (and the rate of flow) will drop off at the other end. However, all the water will eventually come out (the charge). Note that the rate of flow is also reduced before the point of constriction - in fact through the whole pipe. So, resistance does affect current flow through the entire closed circuit. Without the resistor, current flow will spike to infinity and you will get a short circuit. PS. I'm an EE not a physicist...
So can we make an analogy of resistance in a wire with friction in a surface that if there's friction then our speed (in that case charge's speed) is just in control otherwise we can slip on & on due to its absence (there, current can flow on & on & may result to short circuit) ?
@@abhishekmukherjee4063 You cant take surface as a proper analogy because movement in a surface only contains one variable i.e. the speed of the particle and friction whereas the current is a 3 variable phenomenon, the proper analogy will be a flow of water in a pipe,I guess you can also consider throwing a substance below a building from different heights and different air resistances guess that will work too
I still have doubt sir, Considering your example Voltage is pressure on water Current is flow of electron/water particles per unit time ─────────── 𝗟𝗲𝘁𝘀 𝘀𝗮𝘆 𝘁𝗵𝗶𝘀 𝗶𝘀 𝗮 𝗽𝗶𝗽𝗲 𝗡𝗼𝘄 𝗜 𝗵𝗼𝗹𝗱 𝘁𝗵𝗲 𝗽𝗶𝗽𝗲 𝗶𝗻 𝗯𝗲𝘁𝘄𝗲𝗲𝗻 𝘀𝗼𝗺𝗲𝘄𝗵𝗲𝗿𝗲(𝗿𝗲𝘀𝗶𝘀𝘁𝗮𝗻𝗰𝗲) ───●────────── According to your example when the cross sectional area reduces voltage reduces but current stays the same But if we reduce the cross sectional area of pipe somewhere in between the pressure on water increases and so do the current In same case if you remember when we wash our vehicles sometimes we need more pressurised water so we use our thumb on the end as it cause resistance to the flow but due to this action the pressure on water increases (it covers the longer distance that means water particles passing through a cross sectional area increased that eventually means current increased too) So on this case resistance increased the water flow(current) and pressure (voltage) I am totally confused pls help me out
@@PM-eg7lw stay inside the pipe. Use the faucet (tap) as the resistor analogy. Think of the restriction when closing a tap. Don't confuse the issue - because with fluid dynamics there's nozzles, throttling, valves, Bernoulli effect etc. Good luck
i=V/R , higher resistance decreases the flow(volume of electrons) of current passing through it, but any resistor can't eat electrons, so the current on both sides will remain same.
Sir, Some points are missing in the explanation, i.e. The volume of charge will remain same not the speed (velocity). The velocity of the electron doesn't matter, the most important thing is the volume of charge (electrons) passing through the wire cross-section. I just have uploaded a better explanation.
No he was right . He did not said that the dimensions of pipe is changing in between the pipes. If area of cross section is same then the velocity of flow will remain same throughout pipe.
Here a Graduate Physicist. Current in fact descreases when it passes through a resistance. What happens it's the time in which that happen is very small. It's called relaxation time, and during that time charge is accumulated near the surface of the resistance, to make the electric field strong in the resisance (more resistance more voltage falls) and then raise the current , until the circuit reaches the stationary regime and the current is constant. The relaxation time of most conductors are incredible small: copper is 10^-17 and water: 10^-6. So usually in most circuits we neglect this effect. Note: This effect can be approximated with a capacitor in parallel with a ideal resistance. But for computing the capacitance you are going to need to solve the full Maxwell equations numerically for the general case.
@Elias Yes, it's right. Anyways I'm going to leave here a detailed example: - Suppose that you connect two resistors of equal length with resistances R1, R2, where R2 > R1 in series with a battery with voltage V. - Initially, the voltage that falls in each resistor is equal and is V/2 . This means that the current in resistor 1 is I1 = V/(2*R1) and in resistor 2 is I2 = V/(2*R2) . Current in resistance 2 is smaller than in resistance one! - So if this happen , Where does the remaining charge go? Answer: It accumulates between the two resistances. In this case the accumulated charge will be positive. This accumulate charge will create a electric field that increase the voltage that falls in R2 and decreases the voltage that falls in R1. As a consequence, I1 will fall and I2 will rise, until we get the stationary result, which is obtained via circuit theory: V1 = V /(R1 + R2) * R1 V2 = V/(R1 + R2) * R2 And the current is equal in both resistances: I1 = I2 = V/(R1 + R2)
Computational Physics Computational Physics Your explanation best fits for graduate students, for those who have learned Maxwell equations and equation of continuity. But for 10th standard students, his explanation is better.
resistance doesn't store charge therefore the amount of charge entering is same as the amount of charge leaving the resistance. R= breaker ka kamm karta hai that's why 😃
I have one stupid answer..🔥 (READ IT U'll BE Satisfied) Many are saying one word answer as charge conservation.. this isn't true completely. which means what charges are going in are coming out. But current is the rate of flow of charge, the time taken by the charges to complete the journey in case of 0 resistance (no collision) will be lesser than with some resistance. I=Q/t => I inversely proportional to time. Since time taken is increased with adding up of resistance. Hence current (charge per unit time) will decrease. Problem with what sir told is: It should be even after resistance the amount of charge coming out is same as it's going in.. not the current which is time dependent.🙏🏻🙏🏻🙏🏻
Textbooks should never say resistance opposes current....it leads to misconcepts 1)...resistance consumes energy(voltage×q passed) 2)...from where does this energy come?...from collision of electrons during moving under electric field....same energy which is provided by electric field(q×E×d) is lost in collisions... 3)That's why we have V(work done by field that accelerates unit charge in its journey)=iR(energy lost in collisions in resistance)..... You think yourself....all energy provided is lost in collisions.... that is why we have a constant value of i..{i=neavd..constant current means constant velocity and constant velocity means no net work has been done...i.e energy gained=energy lost}.. 4)..resistance is basically dependent on the no. of times electron loses its energy in collisions during its journey...and has to accelerate again....this is from where R=rho L/A comes....if there was no resistance.... all electrons would never collide....no start stop journey....in a fraction, all together will reach low potential.... Giving rise to infinite current(short circuit).....similarly you can think of infinite resistance....journey of electrons never starts really...as they just keep colliding... 5)so the question was....why is current not decreased by resistance?....electron perform start(due to field)-stop(due to collision) motion through out the resistance.....if it decelerates due to collision... Then it also accelerates due to electric field....giving rise to a average value of current, which is same throughout the resistance.... More resistance means...it stops more often then it accelerates giving rise to a low value of current, but even then, it is uniform throughout the resistance.....i.e.overall value of current decreases...but not current itself........ 6)many people also have doubt that V is work done per unit charge While i×r accounts for total no of charges crossing × resistance....how can two things be equal.......one is concerned with single charge and one with all charges crossing!...... Ans is simple......i×r means neAvd×r.....i.e. it has both n and vd(drift velocity) terms in it....say n=1 and vd=2......then it signifies that wow vd is 2 of each electron.....hence good field must be acting on it....hence potential difference is good......now interchange and say n=2 and vd=1....hmm...vd is not high this time of this electron....but heyy!...it is also more crowded this time, thus vd=1 is also commendable here...there must be good potential applied. Which is true as 2×1=1×2....i.e potential is actually same in both cases....overall I conclude by saying....even though i×r includes 'no. of charge crossing term'....,but it has nothing to do with the no of charges crossing.... And only with the crowdness one unit charge feels while moving ......concluding that both potential and ir term are talking about 1 unit charge only....(one of energy gained, one of energy lost)..and hence can be equated to give us beautiful ohms law...which is nothing but a form of energy conservation!!!!... Thankyou😊 Ps: Many people are saying...one word answer is charge conservation....why?... By this explanation....cant charges lose their energy and stay in there afterwards?...i dont seem to get this explanation... resistance is not a pipe which will burst if more water is in it than volume...get me correct please...anyone?
@@jyotiparihar5454 I think that he , want to say that when current pass through that circuit amount ( value of current) differ. Waise mujhe bhi jyada samajh Nahi aaya. Good morning @jyothi
Greater the pipe diameter less the speed, smaller the diameter larger the speed of water. This is due to equation of continuity.plz sir correct the concept as the video is saying it opposite.
I think Here it means, smaller the diameter, greater will be the resistance because of increased collisions, and ultimately the flow will be resisted and slowed down.
@@learningwithtahira5920 But V2 will still be greater than V1 for the smaller pipe so it doesn't matter if the smaller pipe offered more chance of collisions
Hello sir , It would be really really great for all physics students if you take lectures completing the two volumes of “concepts of physics “ , it would be really helpful. Sir as your books ( Two volumes ) are indispensable for all of us , your lectures will be ! Every student aspirant wether Neet or JEE has dream to learn from you , behalf of all students of India Sir do consider my humble request .. Shalem .
see, you can't look at this concept in isolation, to understand let's take an example of simple circuit, 10 V battery, and 1-ohm resistor, according to ohms law, u will get 10 amp current from battery which will pass through 1 ohms resistor, now if u replace 1 ohms resistor with 2 ohms, according to ohms law u will get 5 amps current flowing through battery and resistor, So, a resistor offers resistance to the overall circuit, and current of that circuit is based on that overall opposing force, but once resistor and driving force (here it is the battery) agrees to common current, it flows through the entire system. now coming to, slowing down of charges, there is no point of slowing down of charges, as they already move very little, but it is the message of movement of charges which moves at almost the speed of light.
Though I'm convinced with the logic given by sir but don't u think that there's some mistake occurred in the explanation of continuity equation....?? 🤔 Let me know if u think so...🤞
@@kanyonful if the flow is smoth the speed of water will increase at narrower region. It will make sure same volume of water passes through every cross section whether large or small in a given time.
Yes.But sir NEVER said that speed is SAME in BOTH pipes.He has even used 'v1' for short pipes and 'v2' for larger pipe.The concept is speed whether v1 in small pipe or v2 in large pipe remains same in exit and entry. Hope it helps!!
@@MultiSpidyman You're right, provided the resistance is increasing. Keeping the resistance constant, there wouldn't be any change in rate of flow of charge.
When resistance comes into picture, there some electric field associated with resistance which hinders path of incoming protons (or opposite flowing electrons) & hence there's some change in electric current.
The velocity of electrons may differ according to the value of resistor but not the quantity of charge at both the ends and no accumulation takes place inside the resistor.Even the velocity doesn't matter,only the value of current matters at both the ends.Great sir..
Buy his books and spend 10% on reading and 90% on solving questions. I also did this mistake and I took so so much time just reading and analysing but it's not so deep meaning as much I thought so if you reading his books give more time in solving. 🙏😃
Beautifully explained Sir You are one of the few gems in this world who have core knowledge of Physics and can explain it to students in a very easy and effective way
Sir, i think you taught wrong because a1v1=a2v2,, you said from small cross section velocity of water will be less as compared to large cross section, Actually you are fucking wrong 🙂🙂🙂🙂, Resistance has another thing, don't you know it, 🙂
Ya if the amount of water is constant in both the pipes then water in narrow pipe will have greater speed, it means greater voltage with greater resistance and constant current, hence ohms law is proved🥳 R=V/I
When you put a positive voltage on the ends of a resistor, electrons flow through it. The atoms in the atomic lattice of the resistor also move because of the temperature of the operating area. The moving atoms and electrons often bump together and the electron-flow gets slower, the potential energy(that´s why it's called potential) gets converted to heat. Voltage is just a potential difference. That's also the reason why resistance changes with temperature and why resistors get hot when large currents flow through them.
As much as i respect his teaching i have to say the explanation isn't completely accurate, the reason v1=v2 in the narrow pipe is because the pipe was always narrow from the start that is not the case with resistance, the resistance is offered somewhere in the middle.
Its still valid. Consider resistor as a large pipe connected to a narrow pipe connected which is connected to a large pipe . The velocity in first large pipe is v1 and the narrow pipe has velocity v2 on both ends then the velocitiy of the water comming from the last large pipe must be v1(i.e current going in=current going out)
It's just an analogy my friend it's not 100% explaining what is happening but like I said it's an analogy meaning it's similar to that just not exactly the same
Lol as soon as the resistor is added it is in the same loop so it is a correct analogy, Consider you can walk 500m in a minute in general, but you met a friend and you wasted a fraction amount of time in shaking hands(though not recommended at this time😂) and you were delayed by 10 sec, Right from 0m to 500m your friend can be anywhere in between and still can delay you for ten seconds.If you're going to meet a friend always than you will always be delayed!
I think Resistance works as a bumper on the road. Decrease the velocity, doesn't do changes with scalar Quantitive properties like mass,Just opposing the motion not the quantity...
If the fluid that sir used in the example is an ideal fluid, and considering that same amount of mass flows through both pipes, then shouldn't V2>V1? By equation of Continuity, Area of cross section of pipe is inversely proportional to the velocity of fluid, so shouldn't the velocity of fluid in the narrow pipe be higher? I am confused
But sir, according to the continuity rule, water will flow with a larger speed in a narrower pipe. av = constant. Please clarify your explanation when you say that the speed will be smaller in a narrower tube. Water is incompressible as we know, from the same tap, it will flow swiftly in a narrow tube compared to that in a wider tube.
If the widths at any two points in the pipe are the same, the speeds of water at those two points will also be the same. If you have a pipe whose width varies at different points, the speed of water in the pipe will vary accordingly. Smaller at wider points and larger at narrower points.
Having read & solved HCV books which explained the Concepts of Physics in a lucid way, I always wanted to thank the human behind it! Sir, we are blessed to have you. Thank you so much.
This man is undoubtedly the flag bearer of Indian Physics fraternity. He is expert in solving the problems that appear rather obvious to us.. Really you are great sir... Salute to you and your efforts to make the subject so easy which otherwise is definitely not. That is why you get so much respect from all concerned .
The current basically has no other place to go and therefore it will go through and come out of the resistance. To reduce the current within this setup, you will need to provide a different path for it to flow. Like connecting a parallel wire across the resistance, which can choose to include its own resistance. In that case, the current will split and more current will flow through the path of lesser resistance. Either way, when a current flows across a resistance, we loose voltage across it. And therefore, there is lesser voltage at the point where the current exits from the resistance in comparison to the point where it entered. This is because there was energy expended over the resistance. Now suppose you have a current flowing through a resistance. And suppose you are able to gradually increase the resistance. You will observe that the current also decreases gradually. But whatever current came out of the battery in each instance will flow in and out of the resistance without change. In other words, the battery or voltage source will always decide to push out a current whose value is calculated by first internally _feeling_ the net resistance in the circuit before the current starts to flow. This internal calculation of nature is just ohm's law. This means that if the initial resistance is very very high (imagine a rubber string instead of a copper wire), the voltage source will decide it cannot push a current through the circuit and no current will flow. If however, you now increase the voltage tremendously, there will come a point when it maybe possible to push a current even through this high resistance circuit. But the main idea to understand is - whatever current the voltage source pushes out, after internally seeing the net resistance, it will flow through the loop and complete the circuit.
Best comment. HC sir is unable to explain here. If resistance doesn't oppose the flow of current, than why bulb lights up? The tungsten wire provide great resistance and in the process gets heated up. So here electric energy is being converted into heat and light energy by resistance.
I first started reading Concepts of Physics in 1997. It was an amazing book, clear , concise and very useful. But your videos are at a totally different level altogether sir, unparalleled. 👍 . Great gift for students and that too for Free.
Sir, I'm Naveen Pandey the student of class 10th. Sir when we have the larger cross sectional area the velocity of water becomes decrease when water comes out from a tap or a pipe and when the cross-sectional area of the tap or pipe is small , the velocity of water increases. But sir when we turn on the tap a little, velocity of water from the tap is also little and when we open the tap completely, the velocity of water also increases why this happens?
You can understand by the equation of discharge Q =AV Where, Q= Discharge (flow) of water A= cross sectional area of pipe V= velocity of water So, we can conclude that cross sectional area of pipe is inversely proportional to the velocity of the water
Uh can also say tht resistance is directly proportional to area of cross section so when the Area of Cross section is more thre will b more resistance nd decrease in velocity an when area of cross section is small thre will b less resistance and the velocity will increase If uh agree reply plz...
sir, i have doubt. if restistance due to resistor increase then current decrease.so how current is same, as the current is defined as the rate of flow of charge. i=q/t.due to resistance time is decreases so current should be change where the charge is equal.
I am from Surat My self dinesh sahu In std 12(sci). Q1 - Suppose a part of current wire is connected only one of face part of resistance another part is open, so where the current goes ..and another question Q2-- when suppose 2 ampere current pass from wire and there is too many resistance connected with that wire so the current passing through and output current is decrease but as I say there is so many resistance if i join one of my bulb which run on 1.5 v i connect to wire after 2nd resistance . So what type of curicit ,work and output happen .can the bulb gloww .👍
Your 2nd que have insufficient data If u want to know bulb will glow or not u have to give resistance of resister. And no matter how many resister connected if u connect wire after 2nd resister u have to consider only these 2 ok And also u have to connect cell(battery) in yr circuit 🙂
1st Q.is answered.... 2nd ... It depends on the total resistance of resistors which u have connected to the wire..... If u connect the bulb after 2nd resistor it depends on the first 2 resistors's resistance .....
Both the questions are well answered.... Let me just give some examples. Q1. You plug in your mobile with the USB but forget to turn on the switch. Q.2 Let's say you have displace a pot of rice and you have a cloth with you. Now you will scald your hand or not depends on the thickness and nature of the fabric. (There are better examples possible)
Sir, I'm MOSIN SHAIKH 12th standard student. When we go at some hieght, according to physics there must be gain in energy but we don't fell that we gained energy inspite of these we feel that our energy loss, hope I will get answer of my query. I ask to every teacher from class 10 but no one answer, but my Quiracity still alive!
Our energy is lost bcz of biological factor...... And yes we have gained energy but u can't feel that energy .. u will feel that gained energy when u will fall from that Height.... Relate it with formula (mgh)
Dear MOSIN, When we go at some height , we gain potential energy. But we spend energy from out body to go to that height . The energy that we spent in going to that height was stored in our Muscles in form of ATP. We feel tired because we deplete our body's energy reserves by working. And we feel strong and energetic when our body's energy reserves are at maximum. Conclusion is that, when we gain height we gain potential energy but our body does not feel this gain in potential energy because our body is not working to maintain that pottential energy. Ask your Physics teacher about Types of energies. Ask Biology teacher about ATP. Drop your contact no here. I will help you is they fail.
@@pahlasubscriber6737 if we by lift without using stairs, then there must be gain in PE so where goes stored energy?? We don't feel this too, any answer regarding this one
We are not talking bout fluid mechanics here ...it is not an anology so do not compare that with it ...he is just trying to explain resistance by this .
@@doctorcapacitor7932 it is only an analogy. He knows about fluid mechanics more then anyone in this country.☺️ He would not meant what you understood. The thing you are saying about fluid mechanics only works in laminar flow. But in real life most of the fluids including that from a tap follows turbulent flow. V is inversely proportional to the cross section only in laminar flow. In turbulent flow, v is directly proportional to the cross section . Same as in a thicker wire resistance is less while in a narrower wire resistance is high. This is only an analogy. I am also a student and not sure if we can define flow of current in terms of laminar flow or turbulent flow. Btw, this a very nice question
Sir mention that the pipe is having a same cross section area over here otherwise as narrower the pipe higher the speed will be 【 baurnoulli's principle】
@@milanpatel6912 आप समझे नहीं असल मे मेरी बात। अगर पाइप एक जैसा है शुरुवात और अंत मे तो फ्लो नहीं बढ़ेगा या यूं कहें कि धार न तो तेज़ होगी और न ही निकलने वाली पानी (द्रव्य) की मात्रा। आपको पाइप के एक सिरे को छोटा करना ही पड़ेगा। दूसरी बात जिस वेग( velocity) से पानी अंदर आएगा पाइप के उतनी ही वेग से वो बाहर भी जाएगा क्योंकि पाइप के अंदर पानी के वेग को न हीं बढ़ाया जा सकता है और न हीं घटाया जा सकता है बशर्ते आप पाइप के एक सिरे को दबा कर बारीक या छोटा न कर दें।
Sir is analogy ke hisab se narrow pipe rkhne PR time badal rha he to sir jab resistance lgaenge to bhi time change hona chahiye bs charge same rhna chahiye and time change hoga to current bhi change hoga # please tell about this
But potential difference will change... How can it be possible because ohm's law says that potential difference is directly proportional to the current?
@@Ritiksingh-hk9qx I think this is practically not possible... Because when we connected a fully charged battery to circuit it will discharged after sometime... If this will happen we use battery for infinite time because there is no loss of charge... And as we know that battery used to store the charge!
@@amarchand1190 A battery stores energy in the form of charges.when that charge passes through the resistor(which is current) it looses its energy in the form of heat(which is - current ^2× Resistance× Time) this is the reason why a battery gets discharged after some time(T).
The resistor slows down the flow of the charge per unit area(current density) hence it slows down the current. Dont get confused.It takes a lot of time to understand these things.For a 12th class student whatever HCV sir has explained is sufficient.
Thats what makes you real practical physicist sir! You're awesome as always! 👏 From legendary book concepts of physics 1,2 to your video lectures. We all really miss you in IIT Kanpur campus! 😁 Still we love to brush our concepts from your lectures! Lots of love and respect Muba, geeky Engineer
In the example of pipe, sir says that in 1st pipe, area is more so velocity will be more as compared to second pipe whose area is small. But In principal of continuity we read that Area is inversely proportional to velocity More is the area, less is the velocity So can anyone please help me to make understand this concept🙏🙏🙏🙏
That will apply Only when the force st which water is pushed is same... If the tap is pumping water with same force in both pipes... The bigger pipe will have greater speed... For example... If both taps empty 300 liters of water, the pipe with bigger diameter will do it faster whereas the one with smaller dia. Will take more time... Although water will come out with more pressure form the smaller one🤗😀
Okay so see this. There's this law called conservation of charges, which states that charge can never be created nor be destroyed. So it basically means you can only transfer charge. Assume there's a wire with some resistances connected in series along with a cell. NOW THIS IS IMPORTANT. A cell only provides potential difference between two points of a wire in order to make charges flow(just like if you connect two containers having water filled upto different height, the water flows from the container having higher water level to that of the lower level, so as to make the difference zero, similarly, charges flow from higher potential to lower potential in order to make up for the difference). A cell DOES NOT provide charges, REMEMBER THAT. So now, due to the potential difference provided by the cell, the charges will start to flow. Now if they once start flowing, they will collide with other charges, but will ultimately have to reach the other end of the wire, because as I stated charge can't be created nor be destroyed. So even if there are 'n' number of obstacles in its path, it will have to complete its journey, in order to obey the charge conservation law. Because it has no other place to go to, and it can't stop midway. Hence the phenomenon. You'll get a clearer idea in class 12.
@@uraharakisuke5305 Please tell me what provides charges if not the cell? Is it the free electrons of the conductor? And how does the potential 'difference' is over as we know that non-rechargeable batteries get exhausted after usage? Plz don't feel bad as I am asking you 3 questions at a time.
@@riddhichakravarty4083 yes, you got it right. It's the free electrons of the conductor. And about your second question, see, it's a bit higher than 10th std level so try to understand and if you don't, then chill you'll get it in 12th. So, whenever a cell is connected in a circuit, meaning the circuit is complete, there are some chemical reactions that start occuring inside the cell. These reactions keep occuring until the chemicals used in the cell are completely used up. I'm not getting into much details, cause it would be difficult for me to explain it here and for you to understand as well. If you are still curious though, there's always RU-vid for you. You can watch the mechanism of cells(there are many types of cells btw). And you can ask me too if you encounter any problem in future.
We can not say that air is insulator. Because electricity produced in rain which is of very high voltage is conducted by air. So air is a "BAD CONDUCTOR" of heat and not an insulator. That's the reason behind this.
@@RameshKumar-xd1lm Wrong! Air is an insulator as well as a dielectric. Experiments prove that electric field tends to decrease in the presence of air. But,remains same in the presence of vaccum.
Simply: Just like how small water pipe will draw less amount of water in the first place, similarly higher resistance will draw LESS current in the first place. It's not that current decreases, It's that Current coming is lesser in the first place
1. किसी तार की लंबाई उसकी प्रारंभिक लंबाई की 3 गुना करने पर उसका नया प्रतिरोध कितने गुना हो जायेगा 2. एक चालक तार को खींचकर उसकी लम्बाई 3 गुनी कर दी जाती है उसका नया प्रतिरोध कितने गुना हो जाएगा सर आप के उत्तर का इंतजार करूगा हो सके तो वीडियो के माध्यम से उत्तर दे तो महान कृपा होगी
Amount of water in given time i.e. Discharge(Area×velocity) is constant. Less area will give more velocity to keep discharge constant. Velocity is the distance that water travels in given time, it may change according to area of cross-section. Current(amount of charge in given time) is similar to Discharge which is constant. You're a great teacher sir, highly inspired by your teaching methods.🙏
Sir as we know V=IR so if we increase resistance the voltage also increase so if the resistance stops the current then how is this possible or we thought about an are where there is no resistance then the that means resistance became 0 will the voltage also became 0 ?
Does any one noticed why birds are safe from shocks despite of sitting on wires in which large amount of current flows ??.... This randomly came to my mind ......
Because birds sit on only one wire ! If by any chance the bird touches the other wire at the same time ..it will get electrocuted! Reason:- because of the potential difference creation ! Only the current will flow when there is a potential difference , you can understand it by putting water on one side of a table and slightly tilting it , the water will flow because of the difference in potential ( height) if you leave it as it is , it wouldn't flow same goes with the electricity just here the water is replaced by closely packed electrons in the wire through which the charge transfer takes place ( because of potential ) hence the formula of V=IR takes place V - potential difference, I - current and R resistance ( a constant) that's why birds do not get electrocuted.
Because usually birds don't have any direct connection towards earth and second point they sit just on a single wire/conductor... Hence no circuit is completed neither from wire to wire nor from wire to ground so no flow of current, that's why they don't experience any electric shock.
Why it's difficult to understand? It's a well known fact that current remains same in the entire loop of a circuit. Current is how fast the charge travels, that is speed of charge travel. For e.g: when current enters the resistor, 10 C passed every second, and when it left resistor 5 C passed a point every half second, so rate of transfer of charge remained same because charge density changed. Before entrance less charge carriers (electrons, ions, etc) were travelling with high speed and at exit more charge carriers travelled with low speed (because of congestion), so total charge passing a point per second remained same.
