00:01
In this question, we have three negative charges, a range in a vertical line.
00:06
We want to find the net electric field at point p.
00:11
So to solve the problem, you need to recognize that electric field is a vector quantity.
00:22
So we expect here we have three vectors, three electric field vectors at point p.
00:32
So we need to do vector sum in this case.
00:40
K and then we'll be using the formula for point charge.
00:44
The electric fuel due to point charges is kq over r square.
00:49
Okay, so first we will draw the e -fews at point p due to the three charges.
01:01
Okay, so this is p and so by the two microculum charge negative charge.
01:09
We have a e2 pointing to the left.
01:10
So for negative charges, the electric field point towards the charge.
01:19
Then you have e1 and e3 pointing in this way.
01:23
And then these two angles are the same.
01:26
Because they are symmetrical or an equidistant to a point p is symmetrical to or equal distance or equidistant from the two charges.
01:38
Okay.
01:39
So because of equidistant and same amount of q charge so we know that we want to be equal in magnitude since he is equal to two to two two two two two two two one and q3 then the next thing is by symmetry in the vertical components of e1 and e3 cancel out okay so we we only need to consider the tax components of e1 and e3 and then some there with e2 and that will give us the next electric field at point p.
02:41
So we need, we also need the distances.
02:48
So we have r2, ar2 is 6m from a diagram.
02:54
Okay, we need r1 and r3.
02:56
So r1 is equal to r3, so we just need to find out what it's r2.
03:01
Then we know r3...