How Do You Calculate Electrical Resistance in Complex Geometric Shapes?

In summary, the conversation is about finding the resistance of a circular resistor made out of conducting paper with an outer radius of 4a, inner radius of a, and thickness of 0.15 mm. There is a discussion about whether this is a school work or not, and the importance of knowing the resistivity of the material. The method of solving the problem involves adding an infinite number of circular shells together.
  • #1
nrhk
3
0
How would I find the resistance of said circle

Outer Radius 4a
Inner Radius a

Thickness .15 mm
 
Last edited:
Physics news on Phys.org
  • #2
Are you talking about a hollow cylinder? Are you talking about electrical resistance? If so, don't you need to know the resistivity of the material as well?
 
Last edited:
  • #3
Just in terms of variables, yea I guess you could call it a hollow cylinder

I am talking about electrical resistance.
 
  • #4
What cepheid is trying to tell you is that you need to know the resistivity of the material. Using that information, and the cross-sectional area of your material that is perpendicular to the direction of current flow, will tell you the resistance.

Zz.
 
  • #5
I'm solving the problem in terms of variables

I have a circular resistor made out of conducting paper that has inner radius a and outer radius 4a.

I'm pretty sure I have to add an infinite number of circular shells together to get the total resistance of the object.
 
  • #6
Is this a school work? If it is, it belongs in another forum, and you are usually required to give the full problem first, not your interpretation of the problem. People who are willing to help you with this usually like to see the WHOLE thing first, rather than being given bits and pieces of the problem.

If it isn't, then your geometry is vague.

Zz.
 

1. What is resistance?

Resistance is the measure of an object's ability to resist the flow of electrical current. It is measured in ohms (Ω) and is determined by factors such as the material, shape, and size of the object.

2. How does the shape of an object affect its resistance?

The shape of an object can affect its resistance in multiple ways. Objects with longer lengths or smaller cross-sectional areas will have higher resistance due to the increased distance the current must travel or the decreased amount of space for the current to flow through. Additionally, objects with irregular shapes may have uneven distributions of current, resulting in varying levels of resistance.

3. What are some examples of shapes that have high resistance?

Shapes with high resistance include long, thin wires, narrow tubes, and objects with irregular or jagged edges. These shapes have smaller cross-sectional areas, which restrict the flow of current and result in higher resistance.

4. How can the resistance of an object be measured?

The resistance of an object can be measured using a multimeter, which measures the voltage and current flowing through the object and calculates the resistance using Ohm's law (R = V/I). Alternatively, the resistance can also be calculated using the object's dimensions and material properties, as well as the type of current (AC or DC) flowing through it.

5. How can the resistance of an object be reduced?

The resistance of an object can be reduced by using materials with lower resistivity, increasing the cross-sectional area of the object, or decreasing its length. Additionally, arranging objects in parallel rather than in series can also result in lower overall resistance. It is important to note that some objects, such as heating elements, require a certain level of resistance to function properly, so reducing their resistance may have negative consequences.

Similar threads

Replies
3
Views
479
Replies
4
Views
267
  • Electrical Engineering
Replies
6
Views
1K
  • Introductory Physics Homework Help
Replies
13
Views
1K
Replies
2
Views
2K
Replies
0
Views
70
  • Calculus and Beyond Homework Help
Replies
10
Views
2K
Replies
4
Views
840
  • Introductory Physics Homework Help
2
Replies
44
Views
900
Replies
6
Views
2K
Back
Top