What diameter wire should be used for particular resistance?

Click For Summary
To determine the diameter of nichrome wire needed for a resistance of 16.0 ohms over 49 meters at 20 degrees Celsius, the resistance formula R = ρL/A is utilized. The area A can be expressed as A = πd²/4, leading to the rearranged formula d = √(4ρL/πR). The key challenge is obtaining the resistivity (ρ) value for nichrome at the specified temperature. Participants suggest referring to reliable sources, such as Wikipedia, for the resistivity of nichrome. Accurate calculations will depend on this resistivity value to find the correct wire diameter.
Kastner86
Messages
7
Reaction score
0

Homework Statement



If 49 m of nichrome wire is to have a resistance of 16.0 ohms at 20 degrees Celcius, what diameter wire should be used?

Homework Equations



R = \rho x L / A

A = \Pi d^2 / 4

The Attempt at a Solution



well i know what I'm looking for, that is d (diameter)

and d = \sqrt{}(4\rhoL/\PiR)

I don't know what the value of \rho is.

I know it is supposed to be the resistivity of the material, at a certain temperature, but I have no idea how to include it in the equation.

Please Help!
 
Physics news on Phys.org

Thread 'Magnitude of buoyant force in fluids of different densities'

The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?
View full post »

Similar threads

Electric current and resistance question
  • · Replies 2 ·
Replies
2
Views
2K
Current and resistance of wire heating up water
  • · Replies 4 ·
Replies
4
Views
4K
How does the rise in temperature of fuse wire depend upon its radius?
  • · Replies 12 ·
Replies
12
Views
2K
Lab: Plot graph of resistance, R (in Ohms) versus 1/d^2
  • · Replies 21 ·
Replies
21
Views
11K
Resistance of a Wire at varying temperatures
  • · Replies 1 ·
Replies
1
Views
2K
What is the density of the constantan wire?
  • · Replies 6 ·
Replies
6
Views
2K
Question for the resistance of the wire
  • · Replies 4 ·
Replies
4
Views
4K
Calculate number of turns for an electric heater
  • · Replies 3 ·
Replies
3
Views
2K
Find the resistance of a wire (conductor)
  • · Replies 7 ·
Replies
7
Views
2K
Long distance electrical transmission efficiency
  • · Replies 2 ·
Replies
2
Views
2K