0:00
Hi there.
00:01
Here we have to calculate the total force on the charge q2.
00:06
So let's redraw this system.
00:20
So here q1 is positive, q2 is negative and q3 is also negative.
00:40
So that's why the force which will be deserting on the 4 on the charge 2 will be directed to the left but now we have to use a superposition.
00:50
So the superposition principle tells us that overall force acting on charge 2 equals to the force created by to the force of interaction between the first and the second charge plus the force of the interaction between the third and the second charge so let's show the direction of these two vectors so f1 -2 the force between the first yeah first and the second charge have opposite charges that's why they will be a and f1 .2 is directed to charge 2.
01:31
Meanwhile, q3 and q2 are both negatively charged, that's why they will be experiencing repulsion and f32 is also directed to the right, to the left side of this drawing.
01:48
Now let's introduce x -axis to the left.
01:52
And if when projected on x -axis, f -2, equals to the sum of f -1 -2 and f3 2 so the both of the distances are also the distances equal to r that's why f1 2 equals to k u1 u2 divided by r squared and f32 is q2 q2 2 q2 2 2 q 3 3 divided by r squared times k so here we take absolute chari's because direction of f is already taken into account...