What determins the electrical resistivity of different metals?

In summary, the electrical resistivity of different metals is determined by their structure, specifically the amount of free electrons or holes available for conduction and the mean free path. In general, the resistivity of metals does not vary significantly, but differences can be attributed to the number of outer electrons and density of the metal. In contrast, semiconductors have a different electrical resistivity due to the limited number of free electrons and their ease of conduction. Changes in temperature can also affect the resistivity in semiconductors.
  • #1
lwymarie
90
1
The resistivity arises because the electrons collide with atoms so they flow slower. The resistivity of different metals differ a lot. What determines the electrical resistivity of different metals? It is related to their structure? How?
 
Physics news on Phys.org
  • #2
For some reason I thought it depended upon the amount of electrons in the conduction band. Certainly losses through collisions must play a part. Thus perhaps the amount of electrons/holes that are free to conduct as well as the mean free path.
 
  • #3
It depends greatly on the material, (metals, semiconductors, insulators).
In metals, the argument to increasing electrical resistivity with temperature is the one you pointed (roughly speaking): electron keep bumping into each other , making electron progression more difficult.
In general, the electrical resistivity in metals doesn't vary that much (maybe ~1 order of magnitude).
If I remember correctly, different resistivities in metals are primary due to different metals having a different number of outer electrons, and different densities. (if each atom occupies less space, the number of electrons it provided will have more "bumps" on average).

When we talk about semiconductors, the electrical properties are a lot different. There are not many free electron around, and when you increase temperature, you actually increase the number of electrons available to create the current.
Depending on how easy it is to get out these free electrons from the semiconductors, the electrical resistivity varies, so semiconductors have very different electrical resistivities.
 
Last edited:

1. What is electrical resistivity?

Electrical resistivity is a measure of the resistance of a material to the flow of electric current. It is the property that determines how easily an electric current can pass through a material.

2. How is electrical resistivity measured?

Electrical resistivity is measured in ohms per meter (Ω/m) or ohm-centimeters (Ω-cm). It is usually measured using a device called a resistivity meter, which applies a known voltage to a material and measures the resulting current.

3. What factors determine the electrical resistivity of a metal?

The most important factor that determines the electrical resistivity of a metal is its atomic structure. Other factors include temperature, impurities, and the presence of defects or imperfections in the metal's crystal lattice.

4. How does temperature affect electrical resistivity?

In general, the resistivity of a metal increases as its temperature increases. This is because as the temperature rises, the atoms in the metal vibrate more, making it harder for electrons to flow through the material.

5. Why do some metals have higher electrical resistivity than others?

The atomic structure of a metal plays a significant role in its electrical resistivity. Metals with a more complex atomic structure, such as copper and silver, tend to have lower resistivity than metals with a simpler atomic structure, such as iron and nickel. Additionally, the presence of impurities and defects can also impact the resistivity of a metal.

Similar threads

Replies
8
Views
875
  • Electromagnetism
Replies
16
Views
664
Replies
7
Views
977
Replies
16
Views
1K
Replies
1
Views
1K
Replies
2
Views
697
Replies
3
Views
489
Replies
20
Views
981
Replies
1
Views
833
  • Electromagnetism
Replies
1
Views
606
Back
Top