I with finding a voltage across a Capacitor

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anonx12

Homework Statement


Find the voltage across the capacitor given the data underneath the circuit.

Homework Equations


Voltage Divider Rule
Thevenin Equivalent
Ohms Law

The Attempt at a Solution


I have tried using the Voltage divider rule but I can't seem to get the right answer. The correct answer is 13.61V . I calculated the total current and overall resistance, but I don't know how to arrive where they got. Can someone help me?
 
Attachments
  • Circuit schematic of a DC network with source E1 and resistors R1 to R5, capacitor C1 and inductor L1, with nodes a, b, c and d, alongside a table of component values and units.
    Untitled.png
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Circuit schematic of a DC network with E1 = 35 V source, R1 = 8 kOhm, R2 = 2 kOhm in series with C1 = 6 uF, R3 = 8 kOhm in series with L1 = 16 mH, and R4 = 10 kOhm in series with R5 = 4 kOhm, with nodes a, b, c and d labelled, plus a table of component values and units.


There is no current flowing in the R2 + C1 leg of the circuit so what is the voltage drop across R2 ?
 
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I calculated the equivalent resistance of the ones in parallel, excluding R1. That number is 1435 ohms. I then tried to use the voltage divider rule: Vr2= Req/(R8+Req)
 
I think you missed the point of my question . Please show us your actual workings .
 
Nidum said:
I think you missed the point of my question . Please show us your actual workings .
The voltage across resistor 2 is the same as the voltage across the capacitor. Since the voltage across parallel circuits is the same, we only need to use the voltage divider rule among Resistor 1 and the resistors in parallel. Doing this however, doesn't result in the correct answer.
My worked solutions is : Vr2= (Req/(Req+R1))(35V) Vr2=5.32V Req= ((1/2)+(1/8)+(1/14))^-1
 
anonx12 said:
The voltage across resistor 2 is the same as the voltage across the capacitor

That is not correct . If you can work out why then solving the rest of the problem will be easy .
 
In this simpler problem what is V2 ?
Circuit schematic of a series RC network: resistor R in series with capacitor C, with V1 across the whole series combination and V2 taken across the capacitor.

nb : Assume that the circuit is in a settled condition .