00:01
To calculate the equivalent capacitance between points and b and then find the charge on capacitor is the capacitance of 4 microferrets.
00:09
So let's start with question a first.
00:12
We are going to redraw the circuit, but first we will label the capacitors for the simplicity.
00:18
So let's label them, adding from c1 to c4.
00:25
And let's redraw this circuit.
00:27
So here is point a.
00:28
So c1 is in series with c2 and both of these capacitors are in parallel with c3 and it's so in series with c4 and it's all connected to the battery let's simplify this circuit a little bit so in the way that c1 to 3 is connected in syri to c4 so therefore total capacitance total reciprocal capacitance between points and b is a sum of reciprocal capacitance of one two and three and reciprocal capacitance of c4 so therefore cab equivalent capacitance between points a and b equals to c1 to three multiplied by c4 divided by the sum of c1 to three and c4 so this is our first equation which we've derived and now we are going to find c1 to 3.
01:45
So to find c 1 to 3 we need to look at the capacitors 1 and 2 so they're connected in parallel and series or is therefore 1 over c1 2 equals to 1 over c1 plus over c2 therefore c 1 2 is c1 multiplied by c2 over c1 plus c2 so let's calculate it for the simplicity both c1 and c2 are one micro ferret so therefore its capacitance is half a micro ferret so 0 .50 micro ferret so now now we can calculate c 1 to 3 so c1c2 are in series in parallel to c3 therefore c 1 to 3 is the sum of c 1 2 and c3 or 2 .0 microferret plus 0 .5 micro ferret which is 2 .5 microfret.
03:03
So now we can finally find cab, which is 2 .5 microferret multiplied by 4 .0 microferret divided by 2 .5 microferret plus 4 .0 microferret...