Resistance and the flow in a circuit

In summary, the conversation discusses the flow of electricity through a circuit with identical bulbs. It is mentioned that the flow is the same for bulbs B and E since they are in parallel, but it is unclear how to determine the flow for bulbs A, C, and D. The TA explains that the flow is affected by resistance, but it remains the same for bulbs in parallel. The concept of brightness, or energy dissipation, is also mentioned and it is suggested to find the current and power for each wire segment. The conversation ends with further confusion about the flow in the A, C, and D network.
  • #1
MitsuShai
159
0
Diagram: http://i324.photobucket.com/albums/k327/ProtoGirlEXE/bulbs.jpg

Assume each bulb is identical and have the same resistance to the flow.


I don't know how to determine the amount of flow into and out of bulbs B, E, A, C, and D. (amount as in large flow or small flow)

Suppose that the flow out of bulbs B and E is of size 1 glow (don't mind the unit, this is suppose to be conceptual), how large is the flow through bulbs B and E and why.

So B and E are in parallel, but I don't entirely know how to figure this question out. Is the flow through the bulbs B and E bigger than the flow out because there's resistance in the bulb?
My TA said this, "The flow is the same for two bulbs in parallel. If the flow was different going into the bulb from the flow coming out, then that would imply electricity gets used up and we learned that that isn't true from the last lab."
So I understand what she is saying but, what about bulbs A,C, and D? I initially thought that all the bulbs have the same flow at this point but she also said that the resistance effect the flow, but it effects the flow throughout that branch (I don't know what she means by this).

Now I'm just confused. So the flow IN AND OUT of bulbs B and E are the same because they're parallel. Ok, so the flow must effect bulbs A,C, and D. Bulbs C and D are in series, so the flow must have changed there, but what do I say about bulb A? A is parallel to C and D, so it's the same, but C and D are different?
 
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  • #2
Also, position-wise, I think that bulbs A,C, and D must have greater flow than bulbs B and E, but I don't know how to explain this in "physics terms."
 
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  • #3
Brightness is basically the energy dissipation in a bulb. P = I^2*R. Find the current through each wire segment and compute power for each. For instance, let the emf = V and each bulb has a resistance R. I would begin by finding the equivalent resistance of the circuit.
 
  • #4
WatermelonPig said:
Brightness is basically the energy dissipation in a bulb. P = I^2*R. Find the current through each wire segment and compute power for each. For instance, let the emf = V and each bulb has a resistance R. I would begin by finding the equivalent resistance of the circuit.

No, it's suppose to be conceptual. There's no numbers involved.
 
  • #5
I understand the B and E network now, but I still don't understand the A,D,C network...
 
  • #6
Well, as B and E are parralell and of the same resistance, the flow through is equal, so they equal brightness. Also, the flow into B and E is equal to the flow from above. Also, the flow through A is twice that of the flow through C and D.
 

1. What is resistance in a circuit?

Resistance is a measure of how much a material or component in a circuit opposes the flow of electric current. It is measured in Ohms (Ω) and can be affected by factors such as the material, length, and thickness of the component.

2. How does resistance affect the flow of current in a circuit?

Resistance acts as a barrier to the flow of electric current, causing it to decrease. This is known as Ohm's Law, which states that the current (I) in a circuit is directly proportional to the voltage (V) and inversely proportional to the resistance (R), expressed as I = V/R.

3. How can resistance be calculated in a circuit?

To calculate resistance, you need to know the voltage and current in the circuit. You can then use Ohm's Law to calculate the resistance, or you can use the formula R = V/I. Resistance can also be calculated by measuring the voltage and current and using a multimeter or by using a circuit simulator.

4. How do different components affect resistance in a circuit?

The resistance of a component depends on its material, length, and thickness. Conductors, such as copper wires, have low resistance, while insulators, such as rubber, have high resistance. Longer and thinner components will have higher resistance compared to shorter and thicker ones.

5. What happens to resistance in a series and parallel circuit?

In a series circuit, the total resistance is equal to the sum of individual resistances. This means that adding more components in a series circuit will increase the total resistance. In a parallel circuit, the total resistance is lower than the individual resistances. This means that adding more components in a parallel circuit will decrease the total resistance.

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