Does the Current Stay Constant in Series Resistors Connected to an Insulator?

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Discussion Overview

The discussion revolves around the behavior of current in series resistors connected to an insulator, exploring concepts of resistance, current flow, and the nature of insulators versus conductors. Participants examine theoretical scenarios and practical implications related to electrical circuits.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation

Main Points Raised

  • Some participants assert that in a series circuit, the current is constant through each resistor, but question whether this holds true when the equivalent resistance is that of an insulator.
  • It is proposed that a perfect insulator would have infinite resistance, leading to no current flow, while real insulators allow some current due to imperfections.
  • Concerns are raised about whether current would flow through a bulb connected in series with resistors or an insulator, depending on the current's magnitude.
  • Participants discuss the implications of altering the molecular structure of an insulator, suggesting that it could behave as a conductor or remain an insulator.
  • Questions are posed regarding the conductivity of vacuum and air, with some arguing that even these mediums can conduct current under certain conditions.
  • There is a challenge regarding the relevance of the discussion, as it shifts towards vacuum conductivity and field emission rather than strictly resistors in series.
  • A participant expresses confusion about the terms "constant" and "the same" in relation to current in series circuits.

Areas of Agreement / Disagreement

Participants express differing views on the nature of insulators and the conditions under which current flows, indicating that multiple competing perspectives remain unresolved throughout the discussion.

Contextual Notes

Some statements rely on assumptions about ideal versus real materials, and the discussion includes unresolved questions about the behavior of current in various contexts, such as vacuum and air.

Likith D
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I was told that for resistors connected in series (whatever the equivalent resistance be) the current flowing through a circuit will be a constant
Say i had 'n' number of resistors in series connected to say a battery such that the equivalent resistance was equal to that of an insulator, would i still expect to see current flowing through them
Say i also had a bulb connected along the long chain of resistors (series obviously) would i expect to see the bulb glowing ?
if i were to replace my chain of resistors with an insulator ( the one i mentioned ) would there be still some current flowing ?
if i ripped the atoms of the insulator and say that i got each and every atoms of the insulator in series ( that is to avoid current going in parallel because in atomic atoms don't just form 1d structure but also 3d ) would there be current still flowing through it?
{ Given i don't change potential difference or anything else }
OR ARE MY QUESTIONS VALID AT ALL ?
 
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Likith D said:
Say i had 'n' number of resistors in series connected to say a battery such that the equivalent resistance was equal to that of an insulator, would i still expect to see current flowing through them
A perfect insulator has infinite resistance, and you never reach infinity if you keep adding real numbers. There are no perfect insulators, however, so you always get some current, both with materials called insulators and with arbitrary long chains of resistors.
Likith D said:
Say i also had a bulb connected along the long chain of resistors (series obviously) would i expect to see the bulb glowing ?
Only if the current is large enough.
Likith D said:
if i were to replace my chain of resistors with an insulator ( the one i mentioned ) would there be still some current flowing ?
Yes with a real insulator, no with a theoretical perfect insulator.
Likith D said:
if i ripped the atoms of the insulator and say that i got each and every atoms of the insulator in series ( that is to avoid current going in parallel because in atomic atoms don't just form 1d structure but also 3d ) would there be current still flowing through it?
If you change the molecular structure of an insulator you can get a conductor (e.g. compare diamond and graphite), or an insulator again, so there is no general answer to that question.
 
mfb said:
A perfect insulator has infinite resistance, and you never reach infinity if you keep adding real numbers. There are no perfect insulators, however, so you always get some current, both with materials called insulators and with arbitrary long chains of resistors.Only if the current is large enough.Yes with a real insulator, no with a theoretical perfect insulator.If you change the molecular structure of an insulator you can get a conductor (e.g. compare diamond and graphite), or an insulator again, so there is no general answer to that question.
For Q no one, can't vacuum be a perfect insulator ( because i guess that even tesla coils don"t work in vacuum)
For Q no 3, so whatever is connected to two different terminals, there is some current flowing through it, even air ? ( i mean its a gas! atoms hardly touch each other to make a circuit and yet the tesla coil works in air )
 
Likith D said:
For Q no one, can't vacuum be a perfect insulator ( because i guess that even tesla coils don"t work in vacuum)
You still get some current from thermal emission of electrons, and breakthrough if the electric field is too strong. That is not conductivity in the classical sense, but there is a current flow.
Likith D said:
For Q no 3, so whatever is connected to two different terminals, there is some current flowing through it, even air ?
Right. Especially if the air has some water vapor or dust in it, but even clean dry air conducts a tiny bit of current.
 
mfb said:
You still get some current from thermal emission of electrons, and breakthrough if the electric field is too strong.Right. Especially if the air has some water vapor or dust in it, but even clean dry air conducts a tiny bit of current.
Why does e- travel even in between air ( vacuum ) just to reach the other terminal
 
By vacuum, i mean inter molecular spaces
 
This is no longer about "resistors in series". This is now about vacuum conductivity and field emission. Is this REALLY what you want to learn in this thread?

Zz.
 
ZapperZ said:
This is no longer about "resistors in series". This is now about vacuum conductivity and field emission. Is this REALLY what you want to learn in this thread?

Zz.
nope
 
Likith D said:
nope

Then maybe you want to backtrack a bit and figure out if you really want to ask the question in Post #5, because that is the direction you are taking.

Zz.
 
  • #10
Likith D said:
I was told that for resistors connected in series (whatever the equivalent resistance be) the current flowing through a circuit will be a constant.

I wondered if you are confusing "constant" and "the same in each resistor"?

In a series circuit the current is the same in each resistor eg its constant as you travel along a line of resistors.

It's does not stay constant if you start changing the value of resistors or the number of resistors.

Sorry if you know this.
 

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