What is the Definition of Resistivity and its Relationship to Resistance?

AI Thread Summary
Resistivity is defined as a material property that quantifies how strongly a given material opposes the flow of electric current. It is not directly proportional to any physical dimensions, unlike resistance, which is directly proportional to the length of the conductor and inversely proportional to its cross-sectional area. The relationship between resistivity, resistance, length, and area is expressed by the formula: Resistance = Resistivity * (length/area). Understanding this distinction is crucial for accurately defining resistivity in the context of electrical properties. Clear definitions and relationships are essential for A-level physics revision.
ghostbuster25
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I am revising for my A levels and I have noticed that a common question on the paper is to define RESISTIVITY.

I have looked and looked but found no definitive description or a good definition.

I know the formula but is it right to just say that "resistivity is directly proportional to a conductors length and inversely proportional to its area. and is the resistance electrons face while flowing through it"

Is there any bette way of writing this?
 
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hi ghostbuster25! :smile:
ghostbuster25 said:
I know the formula but is it right to just say that "resistivity is directly proportional to a conductors length and inversely proportional to its area. and is the resistance electrons face while flowing through it"

nooo, that's wrong :redface: …

resistance is directly proportional to a conductors length and inversely proportional to its area …

resistivity (like density) isn't proportional to any dimension :wink:

i'd start by saying that https://www.physicsforums.com/library.php?do=view_item&itemid=241" is a property of a material, and is the resistance … :smile:​
 
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Resistance = Resistivity * (length/area) where resistivity is a material property.
 

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