Resistors in series and current equivalence.

In summary, resistors resist the passage of current through them, but in a series combination, the current through each resistor remains the same since the current entering must also exit. As the current flows through each resistor, there is a voltage drop, represented by V1 = I*R1 and V2 = I*R2. This is due to Kirchoff's second rule, which states that the current flowing into a junction is equal to the current flowing out of a junction. Without this continuous flow of current, the resistors would act as capacitors and the voltage around the loop would not be zero.
  • #1
Prashasti
63
2
"Resistors resist the passage of current through them." Then why the current through each resistor same in series combination? Suppose 'I' current is passing through a system of two resistors connected in series.
1. Won't the first resistor - which is directly connected to the positive terminal of the battery - allow a current with less magnitude to pass through, as compared to the original current with magnitude 'I'?

2. And that the second resistor will not get the current with magnitude 'I'- rather- something of lesser value?
 
Physics news on Phys.org
  • #2
Series looks like: ------[R1]-------[R2]------

Since the current entering on the left is just a bunch of moving charges (electrons), where would the electrons go if they didn't continue on through to the end?

If they didn't the individual resistors would be accumulating charge, and would be called capacitors!

They call it an electric current because it behaves similar to the flow of water: what comes in must go out.

What is changing is the voltage: there is a drop in voltage of V1 = I*R1 as the current flows through R1, and
V2 = I*R2 when it flows through R2. Kirchoff noted that the voltage drop around a loop is always zero - the battery supplies an initial voltage at one terminal (usually +), so V_battery = V1 + V2 if we close the above loop with a battery.

Kirchoff's second rule notes that the current flowing into a junction is equal to the current flowing out of a junction; if there is no junction then the current is unchanged.
 
  • Like
Likes 1 person

1. What is the purpose of connecting resistors in series?

Connecting resistors in series allows for the total resistance to be increased, as the individual resistances add together. This can be useful in controlling the flow of current in a circuit.

2. How do you calculate the total resistance of resistors in series?

To calculate the total resistance of resistors in series, simply add together the individual resistances. For example, if you have three resistors with values of 10 ohms, 20 ohms, and 30 ohms, the total resistance would be 60 ohms (10 + 20 + 30 = 60).

3. How does the current flow in a series circuit with resistors?

In a series circuit, the current is the same at all points. This means that the current flowing through each resistor is equal to the total current of the circuit.

4. Can resistors in series be replaced with a single resistor?

Yes, resistors in series can be replaced with a single resistor that has the same total resistance as the combined resistors. This is known as equivalent resistance.

5. How do you calculate the equivalent resistance of resistors in series?

The equivalent resistance of resistors in series can be calculated by adding together the individual resistances. For example, if you have three resistors with values of 10 ohms, 20 ohms, and 30 ohms, the equivalent resistance would be 60 ohms (10 + 20 + 30 = 60).

Similar threads

Replies
4
Views
1K
Replies
14
Views
1K
Replies
1
Views
823
  • Electromagnetism
Replies
4
Views
1K
Replies
7
Views
1K
Replies
17
Views
1K
Replies
17
Views
1K
  • Electromagnetism
Replies
4
Views
16K
Replies
19
Views
3K
Back
Top