# I with finding a voltage across a Capacitor

• anonx12
In summary, the conversation is about finding the voltage across a capacitor in a circuit using the Voltage Divider Rule and Thevenin Equivalent. The correct answer is 13.61V, but the person asking for help is getting a different answer. The solution involves calculating the equivalent resistance of the parallel circuits and using the voltage divider rule. However, the person has made a mistake and needs to correct it in order to solve the problem correctly.
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

• Untitled.png
8.8 KB · Views: 489

There is no current flowing in the R2 + C1 leg of the circuit so what is the voltage drop across R2 ?

Last edited:
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 ?

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

## What is a capacitor?

A capacitor is an electronic component that stores and releases electrical energy. It is made up of two conductive plates separated by an insulating material, known as a dielectric. When a voltage is applied, one plate becomes positively charged and the other becomes negatively charged. This creates an electric field between the plates, which allows the capacitor to store energy.

## How does a capacitor work?

When a voltage is applied to a capacitor, it charges up until the potential difference between the plates is equal to the applied voltage. Once this happens, the capacitor stops charging and begins to store the electrical energy in the form of an electric field. When the voltage is removed, the capacitor discharges and releases the stored energy.

## What is the voltage across a capacitor?

The voltage across a capacitor is the potential difference between the two plates. Since a capacitor stores electrical energy, the voltage across it will vary depending on the amount of charge stored. The higher the charge, the higher the voltage will be.

## How do I find the voltage across a capacitor?

The voltage across a capacitor can be found by using the formula V = Q/C, where V is the voltage in volts, Q is the charge in coulombs, and C is the capacitance in farads. This formula shows that the voltage across a capacitor is directly proportional to the charge stored and inversely proportional to the capacitance.

## Why is the voltage across a capacitor important?

The voltage across a capacitor is important because it determines how much energy is stored in the capacitor. This can affect the performance of electronic circuits and devices, as well as the overall efficiency of a system. It is also important to consider the voltage across a capacitor when designing circuits to ensure that the voltage does not exceed the maximum rating of the capacitor.

• Introductory Physics Homework Help
Replies
3
Views
587
• Introductory Physics Homework Help
Replies
7
Views
360
• Introductory Physics Homework Help
Replies
3
Views
714
• Introductory Physics Homework Help
Replies
4
Views
1K
• Introductory Physics Homework Help
Replies
3
Views
746
• Introductory Physics Homework Help
Replies
3
Views
338
• Introductory Physics Homework Help
Replies
5
Views
473
• Introductory Physics Homework Help
Replies
4
Views
2K
• Introductory Physics Homework Help
Replies
11
Views
1K
• Introductory Physics Homework Help
Replies
5
Views
1K