Question
Thu April 21, 2011 By: Medha Rai

What is the difference between resistance and resistivity

Expert Reply
Thu April 21, 2011
 
 
Ans-
 
Ohm's law tell us that resistivity of a material is independent of the electric field existing in the material. This is valid for conductors over a wide range of field. And it is denoted by
 
 , where  is resistivity and  conductivity. 
 
The unit of resistinity  is ohm-metre.
 
Resistance of a conductor means ability to block the flow of current in the conductor and it is written as 
 
 
Wher R is the resistance where its unit is Ohm, l is the length of the conductor and A is the area opf cross section.
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