Understanding Capacitors in DC Circuits

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In summary, the conversation is about the behavior of capacitors in a DC circuit. It discusses how a circuit with a DC voltage source, resistor, and capacitor in series is not complete due to the air gap or non-conductive dielectric in the capacitor preventing current flow. However, when a light bulb is added in parallel, the capacitor can discharge and the bulb will light up momentarily. This is because charges can flow from both plates of the capacitor into the circuit through the resistor and voltage source to charge the capacitor, allowing current to flow. This means that even in a DC circuit, current flows in the circuit, not through the capacitor. The conversation also mentions the question of how the circuit is completed, to which the answer is that
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Homework Statement


I have just started learning about capacitors and my question is when you have a DC voltage source connected in a circuit which also has a resistor and capacitor all in series, i.e. a basic charging circuit, is this circuit complete, since there is an air gap or non conductive dielectric in the capacitor there will no flow of current. Let's say to the same circuit we connect a light bulb in parallel to the capacitor than the capacitor will discharge and the light bulb will light up and than go off again. How this be possible if there is no flow current in the circuit since DC current cannot pass through capacitors. How is the circuit formed in this case.
Code:
-------R-----
|                |
V               C
|                |
-------------

-------R------------
|                |        |
V               C      Bulb
|                |        |
--------------------



Homework Equations





The Attempt at a Solution


So in the case of capacitor charging i.e. without the light bulb there will be no current flow in the circuit because the capacitor will not pass DC current, i.e current across resistor R will be zero and in the case of capacitor discharging the current will also be zero since DC current does not flow through capacitor. When you put a capacitor in the DC circuit are you not just creating a break in the circuit than how can this circuit function, i.e. we do not have flow of electrons. The question is what am i missing to understand how the capacitors behave in a DC circuit and how is the circuit completed...
 
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Though current cannot flow through air gap/dielectric in the capacitor, charges can flow from both plates of capacitor (outwards) into the circuit through R and V in order to charge the capacitor. So even in a DC circuit, current flows in the circuit (not through/inside the capacitor) when R and C is connected till C is charged to applied voltage V.
 

1. What is a capacitor?

A capacitor is a electronic component that stores electrical energy in an electric field. It consists of two conductive plates separated by an insulating material called a dielectric.

2. How does a capacitor work?

A capacitor works by accumulating and storing electrical charges on its two plates. When a voltage is applied to the capacitor, the positive charges accumulate on one plate and the negative charges on the other plate. This creates an electric field between the plates, which stores the energy.

3. What are the different types of capacitors?

There are several types of capacitors, including ceramic capacitors, electrolytic capacitors, film capacitors, and variable capacitors. Each type has different characteristics and is suitable for different applications.

4. How do I choose the right capacitor for my circuit?

The right capacitor for a circuit depends on various factors such as the required capacitance, voltage rating, and frequency. It is important to consider these factors and choose a capacitor that meets the specifications of your circuit.

5. What is the unit of measurement for capacitance?

The unit of measurement for capacitance is the Farad (F). However, capacitors used in electronic circuits are usually measured in microfarads (μF), nanofarads (nF), or picofarads (pF).

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