Current flowing from point A in a circuit to point B

In summary, the conversation discusses a circuit with a current of 2A flowing from point A through a 3 ohm resistor, a 20V battery (negative terminal first), a 1 ohm resistor, and a 6V battery (positive terminal first). The potential difference between point A and point B, which is the negative terminal of the 6V battery, is being discussed and it is determined that point A must be more positive than the other side of the 3 ohm resistor for the current to flow. The importance of taking into account the polarity of the battery when calculating voltage drops or rises is emphasized.
  • #1
FADFAD1

Homework Statement


A current at point A of 2A flows through a resistor (3 ohms), a battery of 20V (negative terminal first), another resistor (1 ohm) and a battery of 6V (positive terminal first). What is the potential difference between A and B

Homework Equations

The Attempt at a Solution


I used a negative voltage for when it passes through the first resistor then added 20V through the battery but it doesn't seem right
 
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  • #2
I think you are correst.
I would say that a current of 2A flows from the rest of the circuit through point A into the 3Ω resistor. Point A has to be more positive than the other side of this resistor to make such a current flow.
 
  • #3
FADFAD1 said:
I used a negative voltage for when it passes through the first resistor then added 20V through the battery but it doesn't seem right

That is 100% correct. Just keep going. So far you have..

-(2*3) + 20 ...
 
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  • #4
It might help if you draw the circuit, labeling the voltage drops (or rises) for each device.
You said you did not get the correct answer. (actually you said it doesn't seem right, sorry).
What answer did you get? How did you arrive at that answer? If we can see that, then we can better guide you to where the mistake is.

If current flows through a resistor from left to right, then the left side will be at higher (more positive) potential than the right. Flow through a battery depends on the polarity of the battery. If it goes from negative terminal (through the battery) to positive, then it is a voltage rise.
 
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  • #5
What is point B?
 
  • #6
Asymptotic said:
What is point B?
It sounds like B is the negative terminal of the 6 volt battery.
 

Related to Current flowing from point A in a circuit to point B

1. How does current flow from point A to point B in a circuit?

Current flows from point A to point B in a circuit due to the presence of a potential difference or voltage between the two points. This voltage creates an electric field, which causes the flow of charged particles, known as electrons, through the circuit.

2. What is the direction of current flow in a circuit?

Current flow in a circuit is always in the direction of the electric field, which is from the positive terminal to the negative terminal of a battery or power source. This means that the flow of electrons is from point A to point B in the circuit.

3. How is the amount of current flowing from point A to point B determined?

The amount of current flowing from point A to point B is determined by the voltage or potential difference between the two points and the resistance of the circuit. This relationship is described by Ohm's Law, which states that current (I) is equal to voltage (V) divided by resistance (R).

4. What factors can affect the flow of current in a circuit?

The flow of current in a circuit can be affected by several factors, including the voltage, resistance, and the type of material the circuit is made of. Changes in these factors can alter the amount of current flowing from point A to point B.

5. Can current flow in a circuit without a power source?

No, current cannot flow in a circuit without a power source, such as a battery or a generator. This is because a power source provides the necessary voltage or potential difference to create the electric field that drives the flow of current in the circuit.

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