00:01
Alright, so now in this problem determine the current through each resistor in the circuit shown below.
00:07
So, basically what is the best way to calculate is the kvl.
00:13
We will apply the kvl here.
00:16
Alright, so now let us assume a few currents.
00:20
Right, here is one current flowing through it.
00:24
This is i1 let us say.
00:26
This is i2.
00:29
Right.
00:29
And in this branch it will be i3 let us say downwards.
00:34
This is i3.
00:38
Alright.
00:38
So, now what is the like in we will use the kvl.
00:45
Right.
00:45
So, now this is kvl.
00:47
So, we will apply kvl here.
00:50
Correct.
00:51
So, now on the first loop let us say this is loop 1.
00:56
Loop 1.
00:58
Okay.
01:00
So, applying kvl in both the loops.
01:17
What we are getting now? what is the equation? so, here how you will understand? so, there is like just understand a rule from the ohm's law itself.
01:30
So, summation of all voltages or you can say this battery voltage that is equals that should be equals to summation of ir.
01:41
Right.
01:42
So, when v is going to be positive or negative it could be positive or negative.
01:47
V could be positive or negative and i could also be positive or negative depending on the direction.
01:54
So, basically when you talk about this equation.
01:57
So, you know that when you apply the kvl.
01:59
So, this is from positive to negative.
02:03
Right.
02:04
Outside the circuit that means we are talking about this from here to when you move from here till here.
02:12
Okay.
02:13
So, this is basically what? this should be positive to negative.
02:17
So, then we will take my like positive to negative.
02:21
This will be positive all the way.
02:23
Right.
02:24
And when ir, i is going to be positive then it is in direction of current.
02:35
What is the direction of current? direction of current is from positive to negative.
02:42
So, to like confuse it lesser.
02:49
So, to avoid confusion you can say i am not writing negative one but i will tell you what is the key concept for negative like negative current that is opposite to the direction of current.
03:09
Suppose, if you have like current i1 is flowing backward like from here to here you can say it is now in direction in this direction if it would have been in this direction.
03:23
Correct.
03:24
Flowing through here.
03:25
So, then it would be negative because from the battery terminal you can say that it is moving from negative to positive terminal.
03:34
So, basically ideally it should flow from positive to negative.
03:39
Correct.
03:40
But now if it is flowing through negative to positive that means it is in negative like value.
03:47
Alright.
03:47
So, now we will see.
03:49
So, now here when you make an equation here.
03:52
So, this is summation of v that means you have to take it like this.
03:57
Suppose, you are taking it in direction of this you are taking it this as a like base here and just under making you understand how to make an equation.
04:07
Okay.
04:08
So, now summation of ir will be minus of summation of v that means when v is like battery voltage equals to zero.
04:17
So, that means battery voltage when it is in like direction.
04:21
So, it will be taken as negative direction.
04:23
Right.
04:23
And alternate is also like true.
04:26
Correct.
04:27
So, to confuse less i have not told another thing.
04:31
Okay.
04:32
So, this is how we make an equation.
04:34
Okay.
04:34
So, further we will understand that how to do so.
04:38
So, we will make an equation directly.
04:40
So, this one this was only for understanding that how to solve it.
04:44
Okay.
04:45
Now, this is minus 12 as i already told this is in direction.
04:49
Correct.
04:50
Positive to negative like direction current is minus 2 like positive to negative.
04:58
Correct.
04:58
So, minus 12 plus 4 i 3 because here from here in this branch i 3 is flowing.
05:09
Correct.
05:10
So, now 4 i 3 plus 3 i 1.
05:16
3 i 1.
05:19
Correct.
05:20
So, this is going to be when i 3 and i 2 is combining this is giving us i 1 itself.
05:27
Right.
05:28
So, in the branch of 3 ohm resistor the current flowing through it is i 1.
05:34
Alright.
05:35
So, it should be equals to zero...