Can a wire be called a resistor?

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Discussion Overview

The discussion revolves around whether a wire can be classified as a resistor and whether all circuits require a resistor. Participants explore the implications of wire resistance in various contexts, including theoretical and practical circuit scenarios.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Technical explanation

Main Points Raised

  • Some participants propose that wires have internal resistance, which can be significant in certain applications, while others argue that in ideal circuit diagrams, wires are treated as perfect connectors with no resistance.
  • A participant mentions that while wires typically have resistance, it is often negligible compared to other components, but in some cases, it is important to consider.
  • Examples of circuits without resistors are suggested, including lighting circuits, electric fans, and car starter circuits, though some participants question the practicality of such circuits.
  • There is a discussion about the implications of wire resistance on circuit performance and the potential for electromagnetic radiation acting as an additional resistance.
  • One participant challenges the notion that circuits without resistors are pointless, citing that there are indeed examples of resistor-less circuits.

Areas of Agreement / Disagreement

Participants generally agree that wires have resistance, but there is disagreement on the classification of wires as resistors and the necessity of resistors in all circuits. Multiple competing views remain regarding the implications of wire resistance and the existence of circuits without resistors.

Contextual Notes

Participants note that the context of the circuit (theoretical vs. practical) affects the discussion of wire resistance and its significance. There are unresolved assumptions about what constitutes a resistor and the conditions under which wire resistance is considered negligible.

Additya
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Can a wire be called a resistor? Also do all circuits require a resistor? If no then give an example of a circuit which doesn't have a resistor. Please thanks
 
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Are you asking if wires have internal resistance?
For the second question, I suppose you could have a circuit without a resistor, but I don't see what the point of it would be.
 
Additya said:
Can a wire be called a resistor? Also do all circuits require a resistor? If no then give an example of a circuit which doesn't have a resistor. Please thanks

Your questions are vague.

A "wire" where? A wire in real life, unless it is a superconductor, is a resistor because it has a non-zero value of resistance. However, it has a considerably less resistance than most of the other components of the circuit, so one often ignores that in ordinary cases, but not in all.

A "wire" in a typical circuit diagram are not considered to be a resistor and are idealized to be a perfect connector from one part of the circuit to another.

Draw a battery connected to a capacitor. Is there a resistor in your circuit diagram? How about in real life? Is there a resistance in the wire and in the battery itself?

You need to clarify exactly the scenario and the context of your questions. Otherwise, they are vague.

Zz.
 
Additya said:
Can a wire be called a resistor? Also do all circuits require a resistor? If no then give an example of a circuit which doesn't have a resistor. Please thanks
In most cases, wires have resistance. Some resistors are basically wires. Sometimes the resistance provided wires is important to the function of the circuit - in which case you would expect them to be in the circuit diagram.
Here is a low pass filter - with no resistor:
250px-Lowpass_Pi_Filter.svg.png
 
Additya said:
Can a wire be called a resistor? Also do all circuits require a resistor? If no then give an example of a circuit which doesn't have a resistor. Please thanks
Talk to an Electrical Power Engineer. Despite the fact that their 'wires' tend to be very thick, they are also very long and their resistance accounts for a significant proportion of your Electricity Bill.
On Schematic Circuit Diagrams, we draw lines, joining components and (usually) we treat them as having no resistance because it allows us to do calculations to sufficient accuracy. If wire resistance happens to be comparable with the resistance of those components then we have to take account of the resistance of the wires.
There is actually no practical circuit that you can think of that contains no resistance because components (even superconducting components) are all connected by a practical conducting path. There is another relevant issue. When there is any change of current flowing in a circuit (at switch-on or with AC) some electromagnetic power will be radiated into space. Every circuit acts like a radio antenna, to some extent and that is, in effect, an additional resistor in the circuit.
 
As above.. yes wires have resistance. Sometimes it is negligible and can be ignored, sometimes not.

Many circuits don't have resistors in them. Examples...

House or car lighting circuits
Electric fans or food mixers
Car starter circuit.

Some circuits may have resistors in them but could probably be built without them eg a calculator.
 
Comeback City said:
For the second question, I suppose you could have a circuit without a resistor, but I don't see what the point of it would be.

that's incorrect thinking and as Zz and CWatters have said there are plenty of examples if specific resistor-less circuits

why would you want to introduce additional unnecessary losses in the circuit ?Dave
 
Thread closed for Moderation after confusing necropost...
 

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