Understand Switches & Current Flow in Circuits

In summary, the conversation discusses the concept of current flow and switches in circuits. It is explained that if a switch is opened, current will not flow through a resistor as there is no path for it to go. However, the question arises as to how current can flow into a capacitor in this scenario. The conversation then delves into the workings of a capacitor and how it stores electrons on its plates. It is clarified that current does not actually flow through a capacitor, but rather, the electrons flow into and out of the plates, leaving a charge imbalance.
  • #1
maccha
53
0
I'm a little confused about current flow/switches in circuits. Let's say two resistors are connected in parallel to a battery- if there is a switch between the two resistors on the negative terminal side, and the switch is opened, current won't flow through the second resistor, right? If current can't flow through there because there's no where for it to go, how come it can flow "into" a capacitor"?
 
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  • #2
Could you please show the circuit diagram?

ehild
 
  • #3
Something like this: http://www.gcsescience.com/Switches-Lamps-Parallel-Circuit.gif

if all other switches are closed but S4 is open, current won't flow through the last resistor, right? I didn't understand why but someone explained that it is because current has nowhere to go. I don't understand why, then, current can flow into a capacitor.
 
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  • #4
It is not capacitor but a battery in the picture. The current flows out of the + pole of the battery and back into the negative pole, and can go along the parallel ways through lamps L1 and L2, but if it "chooses" to go across L3 it can not, as the way is broken.

ehild
 
  • #5
Yeah I know I'm just asking hypothetically?
 
  • #6
I believe it has something to do with how a capacitor only stores electrons. A capacitor works via the use of two plates; one hooked up to the positive terminal of say a battery and the other to the negative end. The electrons become stored in the plate attached to the negative terminal of the battery until it becomes equal to the voltage of the battery. If there happens to be a resistor, let's say a light bulb, in between the voltage source and the capacitor then the light bulb will light up (because the electrons flow from the battery to the plate in order to charge the plate) but, soon enough, the bulb will go out (because the plate is storing the electrons).
 
  • #7
a capacitor has a positively and negatively charged plate. One plate has charge flowing into while the other has charge flowing out of it. No current flows through the capacitor -- the charge flowing into it comes from the battery, and the charge flowing out of it comes from one of the previously neutral plates of the capacitor(leaving an effective charge due to holes).
 

1. What is a switch and how does it work?

A switch is an electrical component that controls the flow of current in a circuit. It works by opening or closing a gap in the circuit, allowing or blocking the flow of electricity.

2. What is the difference between an open and closed switch?

An open switch means that the gap in the circuit is not connected, so no current can flow through. A closed switch means that the gap is connected, allowing current to flow through the circuit.

3. How does current flow through a circuit?

Current flows through a circuit in a loop, starting at the positive terminal of a power source, traveling through the circuit components, and returning to the negative terminal of the power source. This flow of current is driven by the voltage difference between the two terminals.

4. What happens when a switch is turned on or off in a circuit?

When a switch is turned on, the gap in the circuit is closed, allowing current to flow through. When a switch is turned off, the gap in the circuit is opened, breaking the flow of current.

5. How does understanding switches and current flow help in circuit design?

Understanding switches and current flow is essential in circuit design as it allows for the proper selection and placement of switches to control the flow of current. It also helps in determining the appropriate wiring and component placement to ensure the circuit functions correctly.

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