00:01
Hello everyone, so let's start with the question.
00:02
So as you can see in the figure, there are two fixed charge that is q1 and q2, okay? so it is placed on a line of axis and the distance between these two charges is 61 .8 centimeter and we have to place the third charge as you can see in the figures in between the two charges so that so that the net force on this charge so that the net force because of this charge will be zero.
00:28
Okay so here we have given some hints that our net force is zero okay so we have to find the location of the charge so that our net force will be zero okay now as you know that our f net is zero okay so we can say that our addition of means summation of all the force equal to zero okay so like i can say that in that the third charge is placed in between the two charges okay so, because of this, because of q third charge, the force acting on charge 1 will be q1 .3.
01:06
And because of charge 3, the force acting on charge q2 will be f23.
01:12
Okay, so i can write, i can write what? i can write that is f1 -3 in vector form.
01:19
That is, also we know the electric force, okay? that is f -e equal to k, q1, q2 by r -square.
01:28
This is our culems law okay so that is f1 3 means on charge the force on charge due to 1 okay so the force on charge 1 due to 3 is i can write k q1 q3 divided by r square okay as you can see the charge means charge having positive value that is positive direction so it will be plus okay i can write f 2 3 that is because of charge 3 the force on charge 2 can be right as k q2 q3 by r square here here our q2 that is having a negative sign that is the charge is negative in negative direction so it will be minus okay so vector sum of this charge force will be vector sum of this force will be f1 3 plus f2 3 equal to 0 now put the value that is kq1 q3 by r square minus k q2 q3 by r square equal to 0 this k q 2 q 3 by r square will be gone right -hand side so k q1 q3 by r square equal to k q2 q3 by r square okay now here common charge will be cancelled that is q3 q 3 q 3 k will be cancelled, that is k here.
02:57
So, q1 divided by r square, q2 divided by r square.
03:04
So here r square is the distance between the charges...
