Current Electricity/Grade-12/JEE/NEET/Physics

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[00:00:20]Hello students, welcome to the student the brand.

[00:00:26]This is your sir.

[00:00:29]Today we are going to discuss about Hello students welcome to this student in the brand. So this is our today we are going to discuss about electric current electricity.

[00:00:47]Current electricity CBSC current electricity grade 12 topic grade 12 topic.

[00:01:01]Okay.

[00:01:03]So grade 12 topic current electricity. Now we are discussing current electricity.

[00:01:16]Current electricity.

[00:01:25]Okay.

[00:01:27]Let's discuss about it.

[00:01:32]The rate of flow of charge.

[00:01:35]The rate of flow of charge is called electric current. That is simple definition, basic definition, fundamental definition.

[00:01:45]Okay. So, rate of flow of charge. Rate of flow of charge, right?

[00:01:54]And the rate of flow of net charge through a unit cross-sectional area per second is called electric current. I = Q byt I = Q byt.

[00:02:14]SI unit of current is ampere. SI of charge is column. SI of time is second.

[00:02:22]Once again the rate of flow of charge G is called electric current. Simple definition.

[00:02:29]So I = Q by T.

[00:02:35]SI rate of current is ampere. SI of charge is column. SI of time is second.

[00:02:43]SI of current is ampere. SI of charge is colum.

[00:02:50]SI unit of time is second right.

[00:02:57]So now 1 ampere is defined as 1 ampere is defined as 1 kum of charge flowing through unit cross-sectional area per second that is called electric current that is sinet of electric current that is known as sinate of electric current understood or not that is known as sinate of electric current.

[00:03:28]Is it clear or not?

[00:03:46]Okay.

[00:03:53]So once again we'll discuss about electric current.

[00:04:10]So now only one electrons flows will you say current is flowing only two electrons flows will you say current is flowing only three electrons flows will you say current is flowing? No, we can't say like this. Yes or no? Only only one electrons flows. We can't say only two electrons flows. We can't say number of charges are moving in the conductor.

[00:04:33]Number of charges are moving in the conductor. Then only we can say current is flowing through the conductor. Yes or no? So those are so here you can see I'm taking this one conductor. This a conductor. So here you can see positive charge, negative charge, positive charge, negative charge like that. So it's going on. So that's why charge is quantized plus or minus any charge is quantized.

[00:05:06]N is the number of charges. N is the number of charges. And one electron, how much charge is present? And one electron, how much charge is present?

[00:05:16]We'll see. and 1 electron 1.6 into 10^ -19 kum and 1 electron 1.6 into 10^ -19 kum in 1 kum how many electrons are present on one electron and one electron 1.6 6 into 10^ -19 kum right in 1 colum how many electrons are present we'll see so 1 kum = 1 by 1.6 into 10^ -19 1 by 1.6 into 10^ -9 kum right yes so now 1 by 1.6 6 into 10^ 19. If you do this one, we'll get 0.625 into 10^ 19. So then 1 kum 6.25 into 10^ 18 electrons are present.

[00:06:27]So I hope it is very clear. Once again check.

[00:06:31]So I = Q byt.

[00:06:35]I = Q byt. The SI unit of current is ampere. SI rate of charge is column. SI unit of time is second. 1 ampere is defined as 1 ampere is defined as 1 kum of charge flowing through unit cross-sectional area per second. SI unit of current is ampere. SI unit of charge is colum. SI unit of time is second.

[00:07:02]Right? Yes. So in the conductor if it is only one electrons flows will you say current is flowing only two electrons flows will you say current is flowing only three electrons flows will you say current is flowing no we can't say like that by passing only one electron two electrons three electrons we can't say current is flowing there are number of charges are moving in the conductor by that only we can say current is flowing okay that's why charge is quantized Next Q = plus or minus N. Q = plus or minus N. N is the number of charges are moving in the conductor and 1 electron 1.6 into 10 - 19 column in 1 column 1x 1.6 into 10 - 19 if 10 goes up. So in the numerator 10 19 1x 1.6 so 1x 1.6 if you do it 0.625 into 109.

[00:08:00]Okay. So then 1 column 6.25 into 10^ 18 electrons are present. Is it clear or not? Yes. So now we will discuss about electrical appliances.

[00:08:16]Electrical appliances.

[00:08:23]Okay. Electrical appliances.

[00:08:41]So I'll discuss about electrical appliances.

[00:08:45]Okay. First one is cell.

[00:08:50]So positive time negative time coming to the battery.

[00:08:55]battery positive term and negative term is cell battery and coming to the third one switch.

[00:09:08]So what is this one? Open switch.

[00:09:14]Open switch. Coming to the fourth one closer switch.

[00:09:20]closer switch.

[00:09:25]Okay. So, one is open switch. Second one is closer switch.

[00:09:32]Okay. First one is cell cell uh cell battery. Open switch.

[00:09:38]Closer switch. Next one.

[00:09:41]So, fifth one resistor.

[00:09:47]Resistor.

[00:09:51]And coming to the sixth one real start either we can take like this or we can consider like this real start.

[00:10:05]Rio start.

[00:10:10]Okay. Once again cell, battery, open switch, closer switch, resistor, reo, start. And the next one is seventh one, amter.

[00:10:24]Ameter, positive terma, negative term, ammeter.

[00:10:32]And coming to the eighth one, voltmeter.

[00:10:38]voltmeter.

[00:10:43]And coming to the ninth one, wire joining.

[00:10:49]Wire joining. 10th one, wire crossing.

[00:10:54]Wire crossing.

[00:10:56]And the last one is bulb. Electrical bulb symbol.

[00:11:02]So 11th one is 11th one is electrical bulb symbol 11th one.

[00:11:16]So electrical bulb symbol understood or not just check cell battery open switch close switch resistor RI start ameter voltmeter wire joining wire crossing and bulb. Okay, first of all we will discuss about resistor.

[00:11:33]Okay, here we have to discuss three points.

[00:11:37]Point number one, resistor.

[00:11:41]Point number one, resistor.

[00:11:45]Point number two, resistance.

[00:11:49]Point number three, ohm.

[00:11:53]And in symbistor is a device. So here resistor is a device which is used to oppose electric oppose electric current in an electric circuit that is a resistor. Coming to the resistance resistance is the phenomena of opposing the electric current. Resistance is the phenomena of opposing the electric current. SI of resistance is ohm. SI of resistance is ohm. And you can see the symbol. This is the symbol understood or not? This is a symbol. So I hope it is very clear right. So now riost start.

[00:12:35]Rio start is a device. Rio start is a device which is used to which is used to regulate the current.

[00:12:44]Rio start is a device here. This is a riost start. Okay. So it is a device which is used to regulate the current without changing the voltage source. Rio start is a device which is used to regulate the current without changing the voltage source. Okay. So coming to the ammeter what is of ameter? Ameter is a device. Ameter is a device which is used to measure electric current. Ameter is a device which is used to measure electric current.

[00:13:23]Okay. So coming to the voltmeter.

[00:13:26]Voltmeter is a device. Voltmeter is a device which is used to measure the potential difference. Voltmeter will be connected in parallel combination.

[00:13:40]Voltter will be connected in parallel combination. Understood or not? So wire joining, wire crossing and the bulb. Is it clear or not? So I hope it is very clear. So just check the electrical appliances.

[00:13:58]Electrical appliances understood or not?

[00:14:02]Yes or no?

[00:14:05]Yes. So one check all the points.

[00:14:10]One check all the points.

[00:14:13]Cell battery open switch.

[00:14:16]Cell battery open switch.

[00:14:20]Okay.

[00:14:41]Okay. So next we will discuss about Next we will discuss about voltmeter potential difference and volt So now we will discuss about electric circuit. Okay. So electric circuit electric circuit electric circuit.

[00:15:47]So electric circuit is nothing but so a closed and continuous path of an electric current. A closed and continuous path of an electric current is known as an electric circuit. an electric circuit. So I'm taking here this the bulb.

[00:16:08]This is a bulb. So a meter and next one uh so battery switch.

[00:16:19]So current is flowing here bulb is glowing like this.

[00:16:26]So here positive term and negative term current is flowing. Understood or not?

[00:16:31]So point number one, point number one, conventional current, conventional current, conventional current and second one is second one is electric current.

[00:16:51]Electric current.

[00:16:54]So conventional current. So what do you mean by conventional current? The flow of positive charges positive charges are moving from positive terminal to negative terminal. Okay. The direction of flow of positive charges will be taken as direction of conventional current. Okay. Here you can see positive charges are moving along.

[00:17:19]So positive charges are moving from positive terminal to negative terminal.

[00:17:24]So that is nothing but high potential to low potential. So that is nothing but high potential to low potential that is nothing but positive terminal to negative terminal positive terminal to negative terminal. Understood or not? I hope it is very clear. So coming to the electric current the flow of electrons.

[00:17:47]So electrons are moving from negative terminal to positive terminal. Okay. So from low potential to high potential. So electrons are moving from low potential to high potential that is negative terminal to positive terminal negative terminal to positive terminal.

[00:18:08]Understood or not? So I hope it is very clear once check here.

[00:18:13]So conventional current the flow of positive charges will be taken as direction of conventional current. So positive charges are moving from positive terminal to negative terminal whereas electrons are moving from negative terminal to positive terminal.

[00:18:29]Right? So there is one question related to this concept. There is one question will electrons moves from positive terminal to negative terminal negative terminal to positive terminal. So electrons will move in the circuit from negative terminal to positive terminal that is low potential to high potential low potential to high potential. So very important is it clear or not? So coming to the next one So one is DC, second one is AC.

[00:19:24]So DC is nothing but direct current. AC is nothing but alternative current. Once again DC is nothing but direct current.

[00:19:34]AC is nothing but alternative current.

[00:19:37]So coming to the DC.

[00:19:40]So both magnitude and direction does not change with respect to time. Both magnitude and direction does not change with respect to time. Okay, that is called direct current. Okay, example for direct current. So we can say point number one cell battery cell battery and DC dynamo DC dynamo.

[00:20:13]Coming to the alternative current.

[00:20:16]Coming to the alternative current. Okay.

[00:20:19]So here both magnitude and direction changes with respect to time. Both magnitude and direction changes with respect to time that is called alternative current. Is it clear or not? Example for alternative current AC dynamo AC dynamo. Is it clear or not? Yes. If the charge is moving in a circular path with frequency F.

[00:20:56]If the charge is moving in a circular path with frequency F, then I = QF.

[00:21:07]I = QF. Is it clear or not? So direct current, alternative current, direct current and alternative current. and their examples.

[00:21:21]And next one, if the charge is moving a circular path with the frequency F, then current is taken I = QF.

[00:21:33]Yes or no? So coming to the next one.

[00:21:38]Next one is drift velocity and relaxation time. So we'll discuss about drift velocity and relaxation time.

[00:22:11]Drift velocity and relaxation time.

[00:22:19]Relaxation relaxation time.

[00:22:26]Okay.

[00:22:29]So what is dive velocity?

[00:22:34]So here you can see I'm taking the conductor. This is the conductor.

[00:22:41]So current is flowing like this.

[00:22:44]Electrical field will be like this.

[00:22:47]Okay. So along the current direction field will be there. So your electrons are moving in the conductor opposite to the electrical field.

[00:23:00]When electrons are moving opposite to the electrical field, it experience some force. Yes or no? So electrons are moving in the field. Okay. So it experience some force that is Q F = Q E R F = E.

[00:23:22]Okay. So when force is acting on the electron then automatically it produce acceleration rate. So if force is acting automatically electron will move. So that's why F = MA F = M A. So now M A = Q that is E. Then a = q by m and e by m understood or not?

[00:23:59]So now we will discuss about drift velocity and relaxation type. Okay.

[00:24:06]Point number one drift velocity.

[00:24:11]Drift velocity under relaxation time drift velocity and relaxation time.

[00:24:29]So here what is a drift velocity? What is a drift velocity? Drift velocity is nothing but so electrons are moving in a conductor right? Electrons are moving in a conductor. So in a closed enclosure that in a closed enclosure within a less space within a less space that in one direction electron should move. All right. If the electrons are moving in one direction that two in less space then what happens? So that there are so many electrons not only one as I mentioned only one electrons flows. Will you say current is flowing? Only two electrons flows. Will you say current is flowing? No not like that. So number of charges are moving in the conductor then latice square will be there. Okay. So wall of the conductor will be there and positive charges are there. So negative charges are there. Then what happens? So electron is moving a closed enclosure.

[00:25:22]One electron is going to eat another electron. That electron is going to eat another electron. So like that keep on bombardment keep on collision takes place.

[00:25:32]I know keep on collisions takes place.

[00:25:34]Here you can observe one thing before collision electron is moving with some velocity after collision so the electron is moving the different velocity. So observe carefully here observe carefully. So here like this. So this electron is going to eat this electron before some velocity will be there. So after collision so the electron will be moving with V_sub_2.

[00:26:03]Then again this electron is going detail electron V3 and like this keep on. So velocity of an electron changes right?

[00:26:13]Velocity of an electron changes before and after right. So the average velocity of an electron moving in a conductor is called drift velocity.

[00:26:24]The average velocity of an electron moving in a conductor is called drift velocity. Is it clear or not? So coming to the next one relaxation time. So as I mentioned as I mentioned what I mentioned so drift velocity is there. So before collision after collision velocity will be varying. So based on the collision so the average the average velocity of an electron moving in a conductor is called drift velocity.

[00:26:52]Right? So between one collision to another collision there is a time gap right? Yes I know. So immediately it won't takes place. Immediately it won't takes place. Right? So one collision after one collision it will take certain time to reach to the next collision. Yes or no? Immediately it won't takes place.

[00:27:10]So uh that two collisions will not takes place regularly.

[00:27:17]So you have to observe one point collisions will not takes place on regular basis. So it depends on it it takes place on random base. Okay. One collision.

[00:27:29]Next, next.

[00:27:38]So between one collision to another collision there is a time gap. That time is called relaxation time. The average time gap between one collision to another collision. The average time gap between one collision to another collision is called relaxation time.

[00:27:58]Right. Yes. So now you can see here that is the drift velocity and relaxation time. So coming to the next one current and drift velocity.

[00:28:10]We'll discuss about current and drift velocity.

[00:28:26]Current current and drift velocity. So we'll discuss that point current and drift velocity.

[00:28:45]Okay.

[00:28:46]So electrons are moving in a closed conductor.

[00:28:51]So here you can see this the conductor area of the cross-section is a this area of the crosssection and this one is area of the cross-section A. So this the length of the conductor this the length L or no length. So current is moving I electrical field also E. Then you can see electrons are moving opposite to the electrical field like this V D SO.

[00:29:24]Now so this particular uh time interval we have to take from here to here how much time that we have to take. So that is a time interval delta t length is there delta t is there velocity is there. So what is the formula? V = velocity equal to displacement by time taken.

[00:29:47]Displacement by time taken. Okay. So, W D = L by delta T. Then L = V D into delta T. So, what about volume? So, what is volume formula? Volume = volume = length into area of the cross-section.

[00:30:06]Volume= to length into area of the cross-section. So now we can see V = L into A. So what is L? V D into delta T into A. So V = V D deltat T into A. This is the volume number of electrons present in the particular volume. Number of electrons present in the particular volume.

[00:30:35]Particular volume. Okay. So that is we can see number of electrons number of electrons understood or not number of electrons equal to small n is electron density small n is electron density v d deltat t into a. So now we know that quantization of charge. What is the quantization of charge? Delta Q = n into E.

[00:31:11]N into E. So delta Q = what is N? Number of electrons. So N V D into A. So here N is number of electrons and E.

[00:31:27]Okay.

[00:31:29]So number of charges. So here electrons we are taking. Now I = delta q by deltat t that is n v data t into a e by delta t delta d delta get cancel n a v d.

[00:31:52]Okay. So what about current density formula?

[00:31:56]Current density equal to current density equal to J value current density = I by A.

[00:32:09]So J = I by A.

[00:32:12]Uh I = how much? N E A V D by A get cancel N E V D. So current density formula is what is the current density formula? J = So what is the current density formula?

[00:32:34]So J = that is not L that is not I this is a volume volume equal to length into area of the cross-section.

[00:32:55]So J = N E V D.

[00:33:02]So there is a formula volume formula that is okay. So I hope it is very clear.

[00:33:16]Just check once current and drift velocity.

[00:33:22]Current and drift velocity.

[00:33:26]So follow one by one.

[00:33:31]So I will post the daily live class regarding class. I'll post in community post.

[00:33:39]Okay. So I'll update in the community post. Check uh check once every time.

[00:33:44]Okay.

[00:33:46]So I'll start the class accordingly.

[00:33:49]So in the community tab in the community post. So I'll post I'll update the regarding a live class. Okay. So if you want to get click on notify notify on live class then you'll get notification immediately. Okay. Click on like button and do uh subscribe and click on like button then automatically you'll get so those who subscribe just click on like button and when I update the link like a live class link you can click on notify me then you'll get the notification whenever I'm taking the live class okay so then you can join to the class on time and uh so you won't miss the topic okay yeah of So I'll try slowly.

[00:35:05]So current density and drift velocity completed.

[00:35:09]So next one we will discuss about next one we will discuss about okay so let's discuss about so based on this there are so many points we going going to discuss.

[00:35:41]Okay. So, Ohm's law is nothing but so the potential difference across the ends of the given metallic conductor is directly proportional to current flowing through it at a constant temperature.

[00:35:59]Okay. So, yes definitely I'll do it. I'll speak in Hindi also.

[00:36:09]So here you can take resistor and voltmeter.

[00:36:19]Understood or not? This voltmeter like this. So current is flowing positive ter negative term. The potential difference the potential difference across the ends of the given metallic conductor is directly proportional to current flowing through it at a constant temperature.

[00:36:44]Okay. So temperature must be constant and physical conditions also same.

[00:36:52]Temperature must be constant and physical conditions also same. So V is directly proportional to I. V is directly proportional to I V = I.

[00:37:05]V is directly proportional to I V = I.

[00:37:11]So here R = from this R = V by I = V by R. So like this we can take understood or not. So here r = v by i = v by r. So we can take all these points.

[00:37:30]So this is very very important. So well um observing the values we have to mention in the table column at the last table column you'll get r = v by okay.

[00:37:42]So now so I hope it is very clear definition.

[00:37:47]Now we can see materials required. We'll do one activity then you'll get clearly about soil materials required.

[00:38:03]What are the materials required? First one four cells.

[00:38:08]Four cells of 1.5 volt of each.

[00:38:12]1.5 volts of each. Coming to the nicrow wire.

[00:38:17]Necro wire.

[00:38:20]Necroire of 0.5 m length. Coming to the third one. Ameter.

[00:38:28]Ameter. Fourth one voltmeter.

[00:38:33]Volultter. And coming to the fifth one switch.

[00:38:38]Switch.

[00:38:50]Okay. So coming to the next one connecting wires.

[00:38:57]Sixth one is connecting wires.

[00:39:05]Connecting wires.

[00:39:08]Understood or not? I hope it is very clear. Just check once four cells 1.5 volts of each necro wire amter voltmeter switch connecting wires.

[00:39:19]Right? So now I'll draw the circuit diagram.

[00:39:24]Circuit diagram circuit diagram drawing here. So you can see circuit diagram now. So four cells 1 2 3 4 So amter next resistor switch voltter I'm connecting here and here one by one we auto connect that way auto connect one by one Okay, here you can see so current is passing current is passing I I so key voltmeter here positive terminal understood or not this is circuit diagram circuit diagram diagram understood or not? Here first one you have to connect one cell.

[00:41:08]You have to connect one cell and note down the reading of amter and voltmeter and connect two cells. Note down the reading of ammeter and voltmeter.

[00:41:19]Second point is two cells.

[00:41:23]Two cells you have to connect the node down reading of amter and voltmeter. And coming to the third one. Repeat the process for three and four cells.

[00:41:34]Repeat the process for three and four cells.

[00:41:38]Okay. So first you have to connect. So this is the first cell and observe the reading of amter and voltmeter.

[00:41:46]Connect two cells. Two cells and observe reading of amter and voltmeter. So repeat the process for so three and four cells and observe the reading of amate and voltmeter.

[00:41:59]Okay. So auto mention in the table or column.

[00:42:13]Okay.

[00:42:15]So table column you have to mention in the table column. So here you can see this a tableler column.

[00:42:26]Serial number of cells amit reading ultimate reading V by I form serial number of cells omit reading ultimate reading V by I = R.

[00:42:43]So 1 2 3 4 1 2 3 4 Okay. So you have to mention in the table column what are the values you observe am I trading ultimate trading and draw the graph. If you draw the graph, so V on yaxis, I on X-axis the graph is straight line.

[00:43:13]The graph is straight line for omic conductors. The graph is straight line for omic conductors. So what do you mean by omiconductors?

[00:43:22]Omic conductors.

[00:43:26]Okay. So omic conductors are the required the conductors which obey ohms.

[00:43:32]The conductors which obey ohms those are called omic conductors. The conductors which does not obey OMSA those are called nonomic conductors. For nonomic conductors the graph is you can observe.

[00:43:45]So V on yaxis I on X-axis the graph is curve.

[00:43:52]The graph is curve for nonomic conductors. Okay. This is for so for nonomic conductors for omic conductors for omic conductor C for omic conductor graph is straight line. So the conductors which obey omsla those are called omic conductors. The conductor which does not obey Ohm's law those are called nonomic conductors. Okay. So these are the graphs understood or not?

[00:44:30]I hope it is very clear. Oh law gives the definition of resistance. Ohms law gives the definition of resistance. So now we will discuss about factors depends on resistance.

[00:44:44]Now we will discuss about factors on which resistance of the conductor depends.

[00:44:52]Factors on which the resistance of the conductors depends.

[00:45:21]Okay. Now you can see so I'm taking a bometer.

[00:45:35]Why it is tried means?

[00:45:39]So it is starting from origin that when potential when potential when potential difference increases current also increases both are directly proportional. That's why for omic conductor the graph is straight line that to starting from origin because we are starting with one cell right after that two cells after the three cells after that four cells. Likewise we are connecting and measuring the values of amter and voltmeter. So initially initial value of ometer is zero. Initial value of voltmeter must be zero. Both both must be zero only. Right? Then we'll get correct readings.

[00:46:17]Okay. So now so battery switch current is flowing like this.

[00:46:34]So now first we have to connect. So first we have to take nicro wire.

[00:46:40]So nicro wire. Okay. Necroire of length L. Necroire of length L. Area of the crosssection. First case second case necroire of length L. And see 2 L and area of the cross-section is here.

[00:46:59]Second case first case so we are taking the nucleum wire of length L and area of the cross-section A in the second case so same neurum wire twice of the length and area of the cross-section is here twice of the length and area of the cross-section is A right. So now you can see and coming to the third case.

[00:47:37]So here you can see of length L necroire of length L and twice of the area of the cross-section.

[00:47:45]Necroire of length L and twice of the area of the cross-section. And coming to the fourth one here fourth one you can observe here I'm taking copper wire. So if you observe in all these three cases, first case, second case, third case, in these three cases, so we took nicroide.

[00:48:11]Okay. But in the fourth case, we took copper V. Okay. We change the material here. If you observe all these three, all these four cases.

[00:48:24]So if you compare first case with the second one, first case with the third one, first case with fourth one, you'll get a different uh understanding. First one you can see so nicro of length L and area of the cross-section normal. So in the second case if you see we are increasing the length in the second case we are increasing the length compared to the first case. In the second case, in the third case, we are increasing the area of the cross-section compared to the first case we are increasing the area of the cross-section. Same length. And but in the fourth case, you can see instead of nikrome wire, so we took copper wire. So here we are changing the material too.

[00:49:13]Okay? So we changed material SR. Now if you connect all these four cases between A and B, if you connect all these wires between A and B, then current reading will be varying. Right?

[00:49:32]Current reading is changing.

[00:49:34]Yes or no? Current reading is changing where in amter like am reading only current value changes. Current value changes. S now now it so how it changes so R is directly proportional to L.

[00:49:55]So resistance is directly proportional to length of the conductor. Means if length increases area length increases resistance also increases. Length is small resistance will be small. Length is more resistance also more. So length is resistance is directly proportional to length of the conductor. So resistance is inversely proportional to area of the cross-section. First one is resistance is directly proportional to length of the conductor. The second one resistance is inversely proportional to area of the cross-section. So now R is directly proportional to L by A. R= row into L by A. So what is R? R is resistance.

[00:50:46]R is resistance and row is resistivity.

[00:50:53]Row is resistivity.

[00:50:58]Is it clear or not? R is R is R is a resistance. Row is a resistivity. Row is a resistivity. Anyway, L we know length of the conductor. A you know area of the cross-section area of the cross-section understood or not? So these are the factors on which resistance of the conductor depends. Now you can see differences we will discuss.

[00:51:24]Differences differences between resistance and resistivity.

[00:51:36]Sometimes we'll get in and similarity also. Fine.

[00:51:40]So resistance here resistance and here we are taking resistivity.

[00:51:51]Resistivity.

[00:51:56]Resistivity.

[00:51:59]Okay.

[00:52:00]So resistance depends on length of the conductor and area of the cross-section.

[00:52:09]So directly proport = A by L.

[00:52:21]Row = R A by L. So here S is and S is oh here.

[00:52:32]So we have to find out row equal to sin of resistance is ohm. Sin of area is m² sin of length is m get cancel meter.

[00:52:45]Understood or not? Sit derivation of sin. It is very very important.

[00:52:51]Sinate of resistivity isometer.

[00:52:55]And coming to the definition, resistivity is equal to definition of resistivity.

[00:53:04]Resistivity is equal to resistance of the conductor per unit length and unit cross-sectional area.

[00:53:13]Resistivity is equal to resistance of the conductor per unit length and unit cross-sectional area. That is called resistivity.

[00:53:22]Sate of resistivity is meter. Sinate of resistivity is meter. Is it clear or not? So meter and a symbol here.

[00:53:38]And coming to the next one, resistance depends on temperature.

[00:53:46]Resistance depends on temperature. Even resistivity also depends on temperature.

[00:53:54]Resistivity also depends on temperature.

[00:53:59]And coming to the resistance depends on nature of the material.

[00:54:06]Nature of the material.

[00:54:12]Is it clear or not? Even resistivity also depends on nature of the material.

[00:54:28]Okay. One check all the points.

[00:54:31]One check all the points.

[00:54:34]Resistance and resistivity.

[00:54:37]R is directly proportional to L. R is inversely proportional to area.

[00:54:43]RA is directly proportional to L by A. R= row into L by A.

[00:54:52]R= row into L by A.

[00:54:57]Okay.

[00:54:58]So, resistance depends on length of the conductor.

[00:55:05]Resistance depends on length of the conductor.

[00:55:11]And resistance depends on area of the cross-section. Resistance depends on temperature.

[00:55:19]Resistance depends on nature of the material.

[00:55:23]Coming to the resistivity, actually resistivity does not depend on length and area but it depends on temperature and nature of the material and assign it is very very important.

[00:55:35]Okay. So coming to the next one.

[00:55:39]So we discuss temperature dependence of resistance.

[00:56:06]So two points I'll tell when temperature increases free electrons in the conductor increases then free electrons move with a greater amplitude then resistance and resistivity in decreases because electrons are moving then automatical current conductivity increases resistance and resistivity decreases. point number one at that particular point after that what what I said when electrons are moving in a closed path in a closed conductor so there are many not only one or two there are many okay if two friends are there they can go so no friendship there okay so every time fighting collisions always collisions only okay one electron will hit another electron that electron another then what happens? Resistance and resistivity increases, conductivity decreases.

[00:57:10]Resistance and resistivity increases, conductivity decreases. Is it clear or not? Yes. So now you can see so r = r + 1 + alpha into t - t then r = r + r into alpha t - t then r - r = r into alpha t - t so alpha = r - r by R into delta T.

[00:57:51]So here what about alpha? Alpha is the temperature coefficient of resistance.

[00:57:57]Alpha is the temperature coefficient of resistance.

[00:58:01]Now row equal to uh rot row minus by into delta t.

[00:58:12]So here alpha here alpha is the temperature coefficient of resistivity. temperature coefficient of resistivity. Understood or not?

[00:58:30]Yes.

[00:58:32]So check once.

[00:58:50]So coming to the next one.

[00:58:56]Resistors are connected in series combination.

[00:59:00]Resistors are connected in series combination and resistors are connected in parall combination. We'll discuss.

[00:59:24]Okay. Resistors are connected in series combination.

[00:59:28]Resistors are connected in Resistors are connected in series combination.

[00:59:45]Series combination.

[00:59:56]Okay.

[00:59:58]So I hope it is very clear. So now you can see I'm connecting 1 2 3 R1 R2 R3 across R1 V1 across R2 V2 across R3 V3.

[01:00:22]So positive negative time postor Okay. So throughout the path current is same. Throughout the path current is same. Yes or no? So here in series combination I = I1 = I2 = I3 = I.

[01:01:18]In series combination throughout the path current is same but potential difference is different.

[01:01:27]Potential difference is different across R1 V_sub_1 across R1 V_sub_1 across R2 V2 across R3 V3 potential difference is different right from Ohm's law V = I V = I so V S = V_sub_1 + V_sub_2 + V3 V = V_sub_1 + V_sub_2 + V3 3 then I R is = I R1 + I R2 + I R3 so I am taking common so R1 + R2 + R3 so I get cancel then RS = R1 + R2 + R3 RS equal to R1 + R2 + R3. Is it clear or not? Now you can see if number of resistors are connected in series combination then RS = NR.

[01:02:41]If number of resistors are connected in series combination RS = NR. Is it clear or not?

[01:02:51]I hope it is very clear. Coming to the par combination if resistors are connected in par combination how it will be? We will see.

[01:03:02]Okay.

[01:03:27]So if resistors are connected in parallel combination.

[01:03:33]So I'm taking parall combination.

[01:03:38]Okay. So here you can see understood or not? So if resistors are connected in parall combination the potential difference is same.

[01:04:51]So then VP = V_sub_1 = V_sub_2 = V_sub_3 = V understood or not but current is dividing here you can see through R1 I1 through R2 I2 through R3 I3 so current is dividing from Ohm's law V = I = V by Right from Ohm's law V = I = V by Yes or no? So then I = I1 + I2 + I3.

[01:05:32]I = I1 + I2 + I3. Then V by RP = V by R1 + V by R2 + V by R3. Shall I take V common?

[01:05:48]1x rp = v I'm taking common 1x r1 + 1x r2 + 1x r3 so we will get cancel so then 1x rp = 1x r1 + 1x r2 + 1x r3 if n number of resistors are connected in parall combination then 1x rp = r by n / r by rp = r by n rp = r by n understood or not.

[01:06:35]Is it clear? Just check once.

[01:06:40]So R1, R2, R3 connected in par is passing. So current is dividing into three parts I1 I2 I3 potential difference is same. So VP equal to through R1 R2 R3 potential difference is same. That's why VP= V1 V_sub_2 V3= V from Ohm's law V = I from Ohm's law V= I = V by R. So potential difference same but current is different right? So IP= I1 + I2 + I3. So overall current if you want to get we have to add 1 2 3 to get current in paral you need to find out I1 + I2 + I3 you have to add all those points. So IP= I1 + I2 + I3 from Ohm's law I equ= to V by R V by RP + V by V by RP= V by R1 + V by R2 + V by R3. So why you taking only V? So here I said right already I mentioned so that's why I'm taking so v get cancel because both in both side ls side and RS side both sides v is same so v I'm taking common get cancel 1x r equal to 1x r1 + 1x r2 + 1x r3 is it clear or not understood or not I hope it is very clear so if n number of resistors are connected in parallel combination if n number of resistors are connected in parallel combination 1x rp equal to n by RP equal to RB.

[01:08:06]Okay.

[01:08:10]Okay. So I hope it is very clear. So coming to the next one.

[01:08:50]Okay. So now we can see when electron is moving through cell.

[01:09:00]So electrolyte is there in the cell as I know. So because of electrolyte the electron experience some force some resistance some opposition.

[01:09:14]Okay. So that is called internal resistance.

[01:09:18]When electrons moving in the conductor like sorry electron is moving in the cell especially in the cell it oppos it experience some opposition.

[01:09:28]Okay. So it experience some resistance.

[01:09:33]So that is called internal resistance.

[01:09:36]That is called internal resistance. I hope it is very clear. Now you can see here.

[01:09:44]So here a this the cell internal resistance R I'm taking here E B okay so now potential difference equal to E minus I current is flowing here current E minus here and one more thing what is E?

[01:10:16]So we have one more doubt what is E?

[01:10:20]So E equal to electromotive force.

[01:10:25]Electromotive force.

[01:10:31]So what is electrootive force?

[01:10:36]So here cell is there again switch resistor.

[01:10:44]So current is passing.

[01:10:47]So we know whenever we close the switch current is start flowing.

[01:10:54]So anyway positive charges are moving from positive terminal to negative terminal.

[01:11:00]We know that immediately whenever you on the switch of positive charge is moving from positive terminal to negative terminal. So what if the positive charge is there at the negative terminal like low potential to high potential.

[01:11:18]Okay. So positive charge is there at low potential. The worker done to bring unit positive charge from low potential to high potential from negative termal to positive terminal. Once again the worker done to bring unit positive charge from low potential to high potential from negative termal to positive terminal is called electromotive force. The influence that makes the positive charge to move from negative terminal to positive terminal.

[01:11:52]The force which is done by the electrical cell here by the cell only the work is done to bring unit positive charge from negative terminal to positive terminal that is called electromotive force. Electromotive force.

[01:12:08]Okay. So I hope it is very clear.

[01:12:12]So understood or not? Yes.

[01:12:22]Okay. So next.

[01:12:42]So now all circuit cannot be reduced into simple series and par.

[01:12:50]Some circuit may not be reduced into series and par that time we will use kit loss.

[01:13:01]Okay. So we'll use kit of loss. Those are one is kit of loss.

[01:13:12]Kitch of loss.

[01:13:16]Okay. One is junction law.

[01:13:23]Junction law. Second one is loop law.

[01:13:30]Loop law.

[01:13:32]One is junction law. Another one is loop law. So what is junction law?

[01:13:37]So junction law is nothing but junction law is nothing but the sum of the current reaching to the junction is equal to sum of the current leaving from the junction. The algebraic sum of all the currents meeting at a junction equal to zero.

[01:13:55]Okay. So I'm taking here here you can observe I1 and here I2 I3 I4.

[01:14:10]Okay.

[01:14:12]So now we can see I1 + I2 = I3 + I4.

[01:14:22]The algebraic sum of all the currents meeting at a junction equal to zero.

[01:14:27]That is about junction law. Junction is a point in the circuit where two or more conductors meet. So coming to the loop.

[01:14:41]So loopla you can observe.

[01:14:45]So point number one as I mentioned emf of this cell electromotive force.

[01:14:53]Okay. So here this the positive terminal negative term.

[01:14:59]So here this the path.

[01:15:02]So when you are moving from negative positive to negative emf of this cell is negative. When you are moving from positive to negative emf of this cell is negative. So coming to the second one when you are moving from negative to positive the emf of this cell is positive because your uh the end point in which direction you are moving what is the last point of yours that is negative terminal here negative potential here you are moving from negative to positive so potential is increasing your potential potential is decreasing. So that's why we are taking like this. And coming to the third one so here resistance and current.

[01:15:59]So I'm taking this the path.

[01:16:02]So the V term is minus I. If you are moving along the current direction, if you are moving along the current direction, the potential drop will be there. That's why V = minus I. Coming to the next one.

[01:16:20]So when you are moving opposite to the current direction then the potential will be neg positive.

[01:16:31]If you are moving opposite the potential is positive. If you are moving in the same direction the potential is negative right? So I hope it is very clear. So this is about kov loopla junction and loopla.

[01:16:49]Okay.

[01:16:51]So next one we will discuss about we will discuss Thank you.

[01:17:31]So now we will discuss about heating effect of electric current. After that we will discuss about cells.

[01:17:39]Cells are connected in series combination.

[01:17:42]Cells are connected in parallel combination.

[01:17:57]Okay.

[01:18:00]So let's discuss about it. Heating effect of electric current.

[01:18:08]Heating Effects of heating effects of electric current heating effect of electric current.

[01:18:35]So now you can see here V = W by Q.

[01:18:42]So here I will discuss two points.

[01:18:46]One is potential difference.

[01:18:50]Potential difference.

[01:18:55]Potential difference is nothing but so here point A point B so positive charge is there. We are doing work. Okay. The work done to bring unit positive charge from one point to another point within the conductor is called potential difference. So V = W by Q 1 volt = 1 J by 1 kum.

[01:19:21]So 1 volt is defined as 1 kum of charge. One J of work is done to bring one kum of charge from one point to another point that is called 1 volt. So coming to electrical potential.

[01:19:37]Electrical potential.

[01:19:42]So electrical potential is nothing but so here you can see this is the required field. This is the positive charge. We are doing work done to bring unit positive charge from infinity to the required field. Work done to bring unit positive charge from infinity to the required field is called electrical potential. Whereas potential difference work done to bring unit positive charge from one point to another point within the conductor. Okay. So here V = W by Q.

[01:20:19]Now, so now V = W by Q from this W = VQ cross multiply V = W by Q W = VQ right now. So P = W by T. What is the W? VQ by T. So we know rate of flow of charge is called current.

[01:20:50]Rate of flow of charge is called electric current.

[01:20:54]Understood or not? So now P = V into I.

[01:20:58]We know energy is equal to P into T. So P = VI into T. We know V= I V = I S V= I. So now H whatever the energy is given to the conductor that will become in the form of heat. So V = I then I into I into T then H = I² RT.

[01:21:32]So this is also known as Jou's law of heating. Heating effect of electric current.

[01:21:40]Heating effect of electric current is also known as Jaw's law of heating.

[01:21:45]Joel's law of heating. Understood or not? So I hope it is very clear. Just check once all the points.

[01:21:53]Just check once all the points. Right.

[01:21:56]Yes. So coming to the next one.

[01:22:16]Next one is cells are connected in series combination. Cells are connected in parall combination.

[01:22:27]Cells are connected in series.

[01:22:31]Cells are connected in Cells are are connected in series combination.

[01:22:43]Cells are connected in series.

[01:22:47]Okay.

[01:22:48]Series combination.

[01:22:57]cells are connected in series combination. So see here I'm taking two cells uh one internal resistance to internal resistance R R MF MF MF.

[01:23:28]So here you can see external resistance.

[01:23:33]So this one is external resistance.

[01:23:37]So current is flowing like this.

[01:23:40]Okay.

[01:23:42]So I hope it is very clear. Now you can see.

[01:23:49]So total emf total emf equal to any total internal resistance or net emf net emf you can take net emf or total also fine net emf net emf equal to any net internal resistance net Internal resistance net internal resistance equal to NR.

[01:24:28]So what about external resistance?

[01:24:32]External resistance.

[01:24:38]External resistance equal to capital R.

[01:24:43]External resistance equal to Okay. So now total total resistance total resistance.

[01:25:17]Okay. So now total resistance total resistance equal to NR + R then I = net emf by net emf by total resistance total resistance So net emf is nothing but n a y by n r + r that is i.

[01:26:05]Okay.

[01:26:06]So coming to the next one cells are connected in parallel combination.

[01:26:14]Now this is about cells are connected in series combination.

[01:26:19]Next we will discuss cells are connected in panel combination.

[01:26:38]Sells are connected in par combination.

[01:26:52]cells are connected in parallel.

[01:26:58]So here you can observe one 2 and third one.

[01:27:07]So here you can observe And one more here.

[01:27:18]So E E R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R R. So that is connected to the external resistance capital R.

[01:27:35]So here current is passing like this.

[01:27:41]So okay.

[01:27:46]So now you can observe find out net emf here net emf equal to net emf equal to e.

[01:28:03]So net internal resistance net internal net internal resistance that is equal to uh R by N normally N / R. So now we are getting R by N. Coming to the external resistance.

[01:28:30]External resistance external resistance equal to capital R.

[01:28:39]External resistance equal to capital R.

[01:28:42]So total resistance total resistance equal total resistance equal to R + R by N R + R by N. Now I = net emf that is E by R + R by N understood or not?

[01:29:15]So this is about cells are connected in series combination and cells are connected in parallel combination.

[01:29:25]Okay. So I hope it is very clear.

[01:29:28]So we'll do a few problems.

[01:29:32]So we'll do a few problems. Let's solve it. Let's try this problems.

[01:29:43]Let's try the problems.

[01:30:26]So, we'll do a few problems. Let's see.

[01:31:13]So we'll try little difficult one.

[01:31:17]Okay. So we'll try little difficult one.

[01:31:21]Okay. So 1 minute.

[01:31:50]Okay. So let's try to do this problem.

[01:31:56]So an electric question an electric an electric bulb is rated electric bulb is rated rated 220 volts and so 100 volts 100 watt when it is operated.

[01:32:30]When it is operated, when it is operated on one volt, the power the power consumed will be okay.

[01:32:58]The power consumed the power consumed will be okay.

[01:33:15]So let's try.

[01:33:19]So is 100 watt.

[01:33:30]B is 75 watt.

[01:33:35]C is 50 watt and D is 25.

[01:33:43]So can you solve it this problem?

[01:33:48]Try it.

[01:33:52]So, so what is the answer? Anyone knows the answer? Let me know.

[01:34:44]100. No.

[01:34:56]So try try once again.

[01:35:04]Try try try again until you get success.

[01:35:11]Try and try again until you get success.

[01:35:19]So it looks very simple.

[01:35:26]No.

[01:35:30]Try try try try try try try try try try try try try try try try try try try try try try try again so it continues right try and try and try again okay so when we will get success but we should not lose the hope we should not lose the hope you have to try okay say warrior will always fight so only the fighting is the Great work that's enough.

[01:36:03]Okay. So we have to be existed in order to get success. Right? So you have to be in the race in order to get success.

[01:36:11]So you you're doing work continuously are facing lot of problems. You couldn't able to stand in the storm. Okay. So storm is very heavy. Wind is very heavy.

[01:36:26]we can't able to withstand once you withstand uh in the storm there is a beautiful weather okay after the storm there is a beautiful weather that is success so meanwhile what we'll do we can't able to withstand in the storm because lot of problems so in all directions so know like a wind so we couldn't able to withstand in the storm.

[01:36:57]So we will move along with the storm. So then finally we can't able to see the beautiful weather after the storm.

[01:37:04]Right? After the heavy wind I know there is a rainbow in the sky a beautiful uh uh like a raining so rainbow will form so like a fresh air and uh the uh sky appears very beautiful.

[01:37:26]Okay. So we can't able to see that is success.

[01:37:31]So wind is wind is moving with a greater speed with a greater force.

[01:37:40]So in that storm if you okay if you withstand you'll get success. So okay. So do fight. Fighting is very important.

[01:38:00]Be in the race. So be in the storm.

[01:38:05]Withstand. So be strong. Be confident.

[01:38:09]So be bold and work towards your goal.

[01:38:13]Definitely you'll get success. Okay. So come to the point.

[01:38:21]So come to the point. So here an electrical bulb is rated right.

[01:38:31]So 2 220 volts and power. So we know that same bulb only they used to write in the second time also same bulb only they used. Now you can see P = V² by R P = V² by R. So R = V² by P. Now R = what is the b 220 volt?

[01:38:59]220 W² + 100.

[01:39:03]How much you'll get?

[01:39:05]How much you'll get? Let me know.

[01:39:10]How much you'll get? 220 by 100.

[01:39:16]220 by 100.

[01:39:20]So can anyone knows the answer? Please do comment in the comment section.

[01:39:27]What is the answer?

[01:39:38]Not 484 is correct or wrong.

[01:39:47]Okay. Then so the same resistance will be so same electrical bulb only right resistance will be same. So P = V² by R.

[01:40:01]Then P V= how much? They operated at 110 vol² by r = 484.

[01:40:12]How much?

[01:40:14]So anyone knows the answer?

[01:40:18]So 25.

[01:40:31]Is it clear or not? Is it correct or not?

[01:40:35]So if it is correct, you can click on like button.

[01:40:40]So you can uh do like, share and subscribe my channel and share to your friends.

[01:40:48]So one more question I'll give. No need to worry about it. So we'll discuss one more question.

[01:41:18]So one more question.

[01:42:02]Yes.

[01:42:15]Question number how many how many because same bulb is used in the second case also in the first case whatever the bulb they used the same bulb they operated on 110 volts initially they operated at 220 so the power is 100 okay so when they operated at 110 volt what is the power consumed. So that is only question.

[01:42:52]Okay. So how many 176 resistors resistors.

[01:43:06]So in parallel I can take parallel So in parallel.

[01:43:20]So are required are required are required to carry to carry 5 ampere on a 220 volt line.

[01:43:44]So can anyone tell me the answer for this question?

[01:43:49]Can anyone tell me the answer for this question?

[01:43:57]So they are connected in parallel.

[01:44:01]They are connected in parallel. So let me know the answer.

[01:44:18]So anyone knows the answer?

[01:44:22]Okay. So I'm also there.

[01:44:26]I will also participate in solving the answer and uh answer to answering to the question.

[01:44:35]So here this is R is given. So current is given or current and potential difference is given we that they connected in parall combination that they connected in parallel combination understood or not. So I = 5 ampere potential difference = 220 vol = 176 ohm.

[01:45:08]Now you are taking this one. Find out the resistance. We know current and potential difference.

[01:45:17]Can we find out the resistance from Ohm's law? V = I R = V by I.

[01:45:28]Okay. So now R = V by I. So V = 220.

[01:45:35]I = Sorry, I = 5.

[01:45:39]I = 5.

[01:45:43]Yeah. How much? 44.

[01:45:47]So, this is Can I take RP? Because they're connected in parallel, right?

[01:45:53]So, shall I take RP?

[01:45:56]Okay. So, I'm taking RP for our understanding sake.

[01:46:00]So, because we will get confused between this one and this one. That's the reason.

[01:46:07]So fine actually if number of number of resistors are connected in parall combination I explained in this in this live class when resistors are connected in parall I given this formula right normally 1x rp= n / rp= r by n rp= r by n. So that's why now you can see RP we got right. So RP = 44 and R = 176 by N. So N = 176 by 44. So what is the answer?

[01:46:53]What is the answer?

[01:46:56]Is it four or any other value?

[01:47:02]So these type of questions are very very important. You need to understand you need to understand what exactly they given in the problem.

[01:47:14]Okay. So after that we can find out one by one.

[01:47:22]Okay. So coming to the next one.

[01:47:25]One more problem. One more problem.

[01:47:42]D.

[01:48:14]So one question is there.

[01:48:33]Okay, done. So difficult one.

[01:49:01]Okay, try this question.

[01:49:46]So try this question. Question number.

[01:49:50]An electrical bulb An electrical bulb is rated is rated at 60 watt 240.

[01:50:13]Calculate Calculate its resistance Calculate its resistance. If if the voltage if the voltage drops drops to 192 volts, Calculate Calculate the power consumed.

[01:50:47]Calculate the power consumed.

[01:50:54]Okay. And the current And the current drawn And the current drawn by the bulb by the bulb.

[01:51:18]So assume that resistance of the bulb is remain safe.

[01:51:23]Resistance R is same.

[01:51:28]So resistance is constant. Shall I take R is constant R remains same.

[01:51:36]Resistance of the bulb is remains same.

[01:51:42]Okay.

[01:51:44]Fine. Try to find out the answer.

[01:51:48]Not the answer.

[01:52:00]What is the answer to this question?

[01:52:08]Resistance is uh how much?

[01:52:13]Okay. Resistance is correct.

[01:52:16]What about power?

[01:52:19]Power is 38.4 watt. Okay. What about current?

[01:52:28]Current current.

[01:52:46]Current zero. Huh? Current how much?

[01:52:56]Okay. So I hope it is so time for time for packup. Okay.

[01:53:10]So I'll come to the next class.

[01:53:15]So with a different topic.

[01:53:19]So answer I'll tell finally I'll give the answer. So you can try to solve it.

[01:53:26]Yeah. So power = to so resistance = 9 960.

[01:53:34]We can use the formula r = v ² by p. Here p = b = 240 p = here p = 60 60 what we can get.

[01:53:56]Next one p value = v² by r formula.

[01:54:01]So here voltage drop they given. So 192 you have to take okay then 192 by² by 960 because 38.4 is what? And coming to the current V I = V by R 192 V by 960 then you'll get 0.2 2 ampere.

[01:54:33]So that is answer.

[01:54:36]So that's enough. So anyway it will take time.

[01:54:40]So thank you so much. So one check the values.

[01:54:45]R = 960 R= V² by P. V = 240 P = 60.

[01:54:51]Substitute in the first equation you'll get and second P= V² back. So they given if the voltage drops to 180 to calculate the power and the current. Here they asked power and the current both they asked. So power equal to so we have to use 192 volts. So in two cases when you are finding power when you are finding current in these two cases you have to use 192.

[01:55:23]Okay. So then 38.4 forward and current is 0.2 ampere.

[01:55:29]So thank you so much for joining attending listening and giving an opportunity to teach. This is youras signing off. Thank you so much. If you like the content if you like the channel do like, share and subscribe to student the brand. We'll see you in the next class with and one more thing so early morning 6:00 I'm taking the class. Okay.

[01:55:53]So I'll update I'll update the uh class timings and the topic in the community post. Just check once. Okay. So thank you so much. We'll see. Check the community post each and every time. So be touch and check the community post. Uh updates will be given based on the live class and timings on the topics and the class. Okay. So thank you so much for joining attending listening my class. This is our sir. So if you like the content, if you like the channel, do like, share and subscribe to show the brand. So drop a word regarding the channel. So spread one word regarding this channel. Inform to everyone regarding the channel. So ask them to watch, ask them to see, ask them to share the channel to everyone.

[01:56:41]So thank you so much. We'll see you in the next class. Thank you.