Which resistor has most current?

In summary: Therefore, the current going through r2 is larger than the current going through r3 and r4. In summary, the path straight ahead has the least resistance and therefore has the most current going through it. The first 4 ohm resistor (R2) has the largest current going through it, followed by the two 4 ohm resistors in parallel (R3 and R4).
  • #1
Linus Pauling
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Circuit: Here's the circuit: there is a 8V battery. The charge leaving it reaches a junction: if the current "turns right" it goes to a 12 ohm resistor (R1) and can then loop around back to the battery, if it goes straight (i.e. takes other path at junction) it runs into a 4 ohm resistor (R2). After the 4 ohm resistor, there are two more 4 ohm resistors (R3 and R4) in parallel (i.e. the equivalent resistor of these two is in series with the first 4 ohm resistor).

Question: Which resistor has the most current going through it?

Relevant equations: resistors in series and in parallel, Kirchoff's loop law

Attempt at solution: If I solve the equivalent resistor for the two 4 ohm resistors in parallel, it's 2 ohms, which is in series with the other 4 ohm resistor, giving 6 ohms. This is less than 12 ohms, so the path "straight ahead" described above (i.e. NOT the path leading to the 12 ohm resistor) is the path of least resistence. Since the first 4 ohm resistor is in series with the equivalent resistor of the other two that are in parallel, then they must have the same current flowing through them by the loop law...

So I was thinking that R2, R3 and R4 would all have the same current through them, but my multiple choice options only include R2, R3, and R4 individually or R3 and R4 together.
 
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  • #2
R2 is in series with the equivalent resistor r3//r4, so the same current goes through them, but this does not mean thant the same current goes through r3 or r4.
Consider the point that connects r2, r3 and r4. The ingoing current through r2 must
be equal to the sum of the outgoing currents through r3 and r4.
 

1. What is a resistor?

A resistor is an electronic component that is used to limit the amount of current flowing through a circuit. It is typically made of a material that can resist the flow of electricity, such as carbon or metal.

2. How does a resistor affect current?

A resistor reduces the amount of current flowing through a circuit by converting electrical energy into heat. This is known as resistance and is measured in ohms (Ω). The higher the resistance, the lower the current.

3. Which resistor has the most current?

The resistor with the least amount of resistance will have the most current. This is because less resistance allows for a greater flow of current through the circuit.

4. What is the relationship between voltage and current in a resistor?

Ohm's Law states that the current through a resistor is directly proportional to the voltage applied across it, and inversely proportional to the resistance of the resistor. This means that as the voltage increases, the current also increases, but as the resistance increases, the current decreases.

5. How can I determine the resistance of a resistor?

The resistance of a resistor can be determined by using a multimeter, which measures the voltage and current in a circuit. By dividing the voltage by the current, you can calculate the resistance in ohms. Alternatively, the resistance value may be indicated by color-coded bands on the resistor itself.

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