- #1
Mutaja
- 239
- 0
Homework Statement
In a plate capacitor, the plates has a area of ##100cm^2## and a distance of 3mm. The insulation between the plates is a 1mm glass plate (εr = 10), a 0.5mm thick mica plate (εr = 5) and the rest is air. The insulation layers is parallel with the capacitor plates. The capacitor is connected to a 100V voltage supplier.
a) find the voltage across the layers.
b) How big is the field strength in each layer?
Homework Equations
The Attempt at a Solution
For a.
I'm using the current divider rule.
Vglass = [itex]\frac{\frac{10*0.01m^2}{0.004mm}}{\frac{10*0.01m^2}{0.004mm}+\frac{5*0.01m^2}{0.0035mm}+\frac{0.01m^2}{0.003mm}}[/itex] * 100V = 56.88V.
This answer seems about 10x larger than it should be - which is why I'm pretty sure that I'm on the right track here. Well, that's only based on the fact that the random chance that I've come up with a completely wrong formula and get an answer that is almost exactly 10 times larger than what it should be, is fairly low.
What am I missing here?
As always, and feedback is very much appreciated.
- Mutaja.