00:02
Alright, so in this problem we have a capacitor which is filled in by some materials and it is connected by another external battery.
00:21
So the conditions we know is we know the area which is 100 cm squared and we know the charge stored on the surface which is 8 .9 times 10 to the negative 7, and we also know the electric field inside is 1 .6 times 10 to the 6 watt per meter.
00:45
So for part a, we want to find out the electric constant of the material.
00:51
So to figure this out, we can utilize the definition of the capacitance.
00:56
So c equal to q over b, right? and also for the parallel plate capacitor, we have expression for c, which is kb, epsilon knot, a over d, right? so in that way, we can basically obtain the expression for kappa.
01:18
So kappa equal to qd divide by v, absolute not, and times a.
01:26
And remember, the v over d just gave you the electric field.
01:30
So equal to q e, epsilon, a.
01:35
All right.
01:36
So now come back to the conditions...