What is the purpose of resistors in electrical circuits?

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Discussion Overview

The discussion revolves around the purpose of resistors in electrical circuits, focusing on their role in current limitation, voltage division, and manipulation of electrical power. Participants explore both series and parallel configurations of resistors and their implications for circuit behavior.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants propose that resistors limit the current in a circuit, affecting the overall current flow when placed in series.
  • Others argue that while the current entering a resistor is the same as the current exiting, the presence of the resistor alters the current that would flow without it.
  • A participant suggests that resistors act as loads in a circuit, manipulating electrical power, and that understanding this manipulation is part of electronics study.
  • One participant notes that resistors in series can be useful for achieving different voltages at various points in a circuit, depending on the current and resistance.
  • Another participant mentions the use of resistors as voltage dividers and in combination with capacitors in RC circuits to achieve desired frequency responses.

Areas of Agreement / Disagreement

Participants express multiple competing views regarding the role and purpose of resistors in circuits, with no consensus reached on a singular explanation.

Contextual Notes

Some statements rely on assumptions about circuit configurations and the definitions of terms like "load" and "voltage divider," which may not be universally agreed upon.

Larrytsai
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I looked this up, and found that it limits the current going through, but say if we have a c ircuit with a power source and 1 resistor, the current through the resistor is the current coming out of the resistor.

I know if you hook the resistor up in parallel that is not the case, but in some circuits I have seen, they hook up the resistor in series, but what is the point?
 
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The current going in certainly is the current going out, but that doesn't mean it's the current you'd get without the resistor.

Once the resistor is placed in you limit the entire circuit current immediately (series).
 
Hmmm. The broad, generic answer that your question seems to seek would be something like this: Without any resistance in the circuit, what you have, of course, is a dead short. The purpose of any electrical circuit, electronic or otherwise, is to power some kind of load which itself provides an amount of resistance and is thus some form of resistor. From this it would seem reasonable to say that the purpose of any resistor in a circuit then is to act as a load with a view to in some way manipulating the electrical power. To understand the reasons why you would want to manipulate the electrical power in the various ways possible is of course, a question of the study of electronics. Is that what you were looking for?
 
Larrytsai said:
I looked this up, and found that it limits the current going through, but say if we have a c ircuit with a power source and 1 resistor, the current through the resistor is the current coming out of the resistor.

I know if you hook the resistor up in parallel that is not the case, but in some circuits I have seen, they hook up the resistor in series, but what is the point?

Hooking them up in a series could be useful if, for example, you need different voltages at different parts of the circuit, as there will be a certain voltage after the resistor depending on current and resistance, i.e. if you want to use devices on the same line that require different voltages.
 
As SamirS says, as a voltage divider. Also in combination with a capacitance, as an RC circuit to provide a desired frequency response.
 

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