Resistors in series and current equivalence.

AI Thread Summary
Resistors in series allow the same current to flow through each component because the electric current behaves like a continuous flow, similar to water, where the same amount of charge must exit as enters. When current 'I' passes through two resistors, R1 and R2, the voltage across each resistor drops according to Ohm's Law (V = I*R), but the current remains constant. If the current were to decrease after the first resistor, it would lead to charge accumulation, which contradicts the nature of current flow. Kirchhoff's laws reinforce this concept, stating that the current entering a junction equals the current exiting, and in a series circuit, there are no junctions to alter the current. Thus, while voltage changes across resistors, the current remains equivalent throughout the series connection.
Prashasti
Messages
63
Reaction score
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
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
I was using the Smith chart to determine the input impedance of a transmission line that has a reflection from the load. One can do this if one knows the characteristic impedance Zo, the degree of mismatch of the load ZL and the length of the transmission line in wavelengths. However, my question is: Consider the input impedance of a wave which appears back at the source after reflection from the load and has traveled for some fraction of a wavelength. The impedance of this wave as it...
Back
Top