Understanding the Importance of Resistors in Electrical Circuits - Explained

In summary, resistors are necessary in a circuit because all materials have resistance, but in most cases, the resistance of wires is negligible and can be ignored in calculations. However, in certain cases, such as power lines, the resistance of the wiring must be taken into account. Resistors serve to regulate the flow of current, not for computational ability. They are necessary when a specific amount of resistance is needed, which often exceeds the resistance of a simple wire.
  • #1
cscott
782
1
A question I've never had fully answered:-

Why are resistor(s) necessary in a circuit in the sense that wires themselves (in my mind) should have resistance since they constitute material just like resistors themselves?

Thanks
 
Last edited:
Physics news on Phys.org
  • #2
cscott said:
A question I've never had fully answered:-

Why is are resistor(s) necessary in a circuit in the sense that wires themselves (in my mind) should have resistance since they constitute material just like resistors themselves?

Thanks
I think what you asking is that shouldn't the wires in a circuit have a resistance?

The answer is of course, yes! All materials (except super conductors) have a resistance and therefore should technically be accounted for in calculations. However, such calculations become tedious and generally, since wires are good conductors the error in ignoring the resistance of the wiring is negligible. There are some cases, such as power lines, where the resistance of the cabling must be taken into account.
 
  • #3
But doesn't this imply that we add resistors to a circuit just for computational ability?

Can I consider a circuit with a capacitor and a wire taken with capacitance C and and resistance R?

Why can't the resistance of the wire take [tex]R= \rho \cdot \frac{L}{A}[/tex] like a "resistor" that we'd typically use?
 
  • #4
It can be, but this is a ridiculously low resistance in almost all cases. Therefore you're likely to mess up your circuit somehow. When you try to discharge a capacitor through just a wire, you will see sparks fly. Hook just wire up to a battery, and it will heat up very quickly and drain the battery. Resistors serve to regulate the flow of current, not for computational ability.
 
  • #5
WIRE = Wicked Infinitesimal Resistance Element.

Sometimes, a wire has sufficient resistance on it's own- a lightbulb filament is an example.
 
  • #6
Resistors are necessary in electronic circuits when the value, or amount, of specific resistance to electron flow is needed. This oftentimes exceeds the amount of resistance of a simple "wire"
 
  • #7
I get it now. Thanks all.
 

Related to Understanding the Importance of Resistors in Electrical Circuits - Explained

1. What is the purpose of resistors in electrical circuits?

Resistors are electronic components that are used to control the flow of current in a circuit. They are designed to resist the flow of electricity and reduce the amount of current that passes through a circuit. This helps to regulate the voltage and prevent damage to other components in the circuit.

2. How do resistors work in an electrical circuit?

Resistors work by using a material with high resistance, such as carbon or metal, to limit the flow of electric current. The resistance is measured in ohms and is determined by the material, length, and thickness of the resistor. When a voltage is applied to the resistor, it creates a potential difference and restricts the flow of current through the circuit.

3. Why are resistors important in electrical circuits?

Resistors are important in electrical circuits because they help to control the flow of current and prevent damage to other components. They also help to regulate the voltage and maintain a stable current throughout the circuit. Without resistors, the flow of current could become too high and cause overheating or even failure of the circuit.

4. How are resistors used in different types of circuits?

Resistors are used in various types of circuits, such as in series and parallel circuits. In series circuits, resistors are connected one after the other, creating a single path for the current to flow. In parallel circuits, resistors are connected side by side, creating multiple paths for the current to flow. The value of the resistors can also be adjusted to control the current and voltage in the circuit.

5. Can resistors be replaced with other components in a circuit?

No, resistors cannot be replaced with other components in a circuit. Resistors are specifically designed to control the flow of current and regulate voltage, and other components do not have the same properties. Using the wrong component in place of a resistor can cause damage to the circuit or produce inaccurate results.

Similar threads

I Is the Poynting Vector Field the Only Factor in Energy Flow in Circuits?
    • Electromagnetism
Replies
16
Views
1K
I Physics domain analysis of Voltage drop in series resistor
    • Electromagnetism
Replies
7
Views
1K
I Can current flow in an open circuit?
    • Electromagnetism
Replies
4
Views
1K
I Is this example incorrect in Agawal's book on electric circuits?
    • Electromagnetism
Replies
3
Views
894
I An attempt to understand the associated variable conventions in circuits
    • Electromagnetism
Replies
1
Views
855
Electric field in a circuit with a DC source
    • Electromagnetism
Replies
2
Views
10K
Why does current choose the short circuit path?
    • Electromagnetism
Replies
18
Views
4K
Electrical potential energy questions for a battery circuit
    • Electromagnetism
Replies
4
Views
897
Electromotive Force, Batteries, Resistors, and Potential Differences
    • Electromagnetism
Replies
17
Views
1K
Charge distribution in a resistor with a current
    • Electromagnetism
Replies
4
Views
16K

Hot Threads

Recent Insights

Back
Top