00:01
So in this problem, what we're looking at is a pair of charges, a pair of point charges.
00:07
And in this problem, we have q1, which is stationary in q2, which moves from point a to point b.
00:14
Now, in the problem, we're told the electric potential energy of the pair of charges initially, while q2 is at point a, is 5 .4 times 10 to the negative 8 joules.
00:24
And we're told that to move q2 to point b, its new position, an electric force, on the charge does negative 1 .9 times 10 to the negative 8th joules of work.
00:36
So now what we want to do is we want to find what the electric potential of the pair of charges is when q2 is at point b.
00:43
So we're basically looking for ub, this unknown here.
00:49
So what will we need to know in order to solve this problem? so this problem deals with electric potential energy, which we can denote as you and work, which we can denote as w.
01:01
So so we know that electric force caused by any collection of charges is a conservative force.
01:09
And the work done by electric force on a charged particle can be represented by the change in potential energy.
01:16
So what does this mean if we were to write it out in an equation form? so this means that the work it takes to move a particle from point a to point b, it's going to be equal to the electric potential energy at point a minus the electric potential energy.
01:32
Potential energy at point b...