The figure below shows a section of circuit which has four air-filled capacitors

Question

The figure below shows a section of circuit which has four air-filled capacitors. (This section is connected to a larger circuit.)

The graph above the circuit shows the electric potential V plotted as a function of position x along the upper branch, through capacitors 1, 2, and 3. The far right side has been (arbitrarely) set to V=0 to facilitate graphing.

Similarly, the graph below the circuit shows the electric potential V as a function of position x along the lower branch, through capacitor 4.

If capacitor 3 has a capacitance of 0.70 µF, answer the following below:

(a) What is the capacitance of capacitor 1?
C1 = in µF

(b) What is the capacitance of capacitor 2?
C2 = in µF

(c) Find the potential stored by each of these capacitors:
PE1 = in J
PE2 = in J

(d) Concept: Complete the following statement.
Capacitor 1 stores ---Selectone---     more       less          the same amount of total energy (compared to capacitor 2) because:
its plates have ---Selectone---         more        less         the same amount of charge carriers, each storing ---Selectone---          more           less               the same amount of energy (compared to those on capacitor 2).

(Make sure your answers agree with your calculations!)

Explanation / Answer

a)
charge on Q3 = V3*C3

= (12- 2 - 5)*0.7

= 3.5 micro C

charge on C1 = charge on C2 = charge on V3 (beacuse they are connected in series)

C1 = Q1/V1

= 3.5*10^-6/2

= 1.75 micro F <<<<<<----------Answer

b) C2 = Q2/V2

= 3.5*10^-6/5

= 0.7 micro F <<<<<<----------Answer

c) PE1 = 0.5*C1*V1^2 = 0.5*1.75*10^-6*2^2 = 3.5 micro J

PE2 = 0.5*C2*V2^2 = 0.5*0.7*10^-6*5^2 = 8.75 micro J

d) Question is not clear.

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