Question

calculate the resistivity of a material of a wire 2 m is made. when operated at 25 °c at 27 ohm​

Answer 1

Answer:

Explanation:

Given :   R=2Ω            l=1 m            d=0.4 mm =0.0004 m

Cross section area of wire       A=  

4

πd  

2

 

​  

=  

4

π×(0.0004)  

2

 

​  

=1.256×10  

−7

 m  

2

 

Resistivity of the material       ρ=  

l

RA

​  

 

∴   ρ=  

1

2×1.256×10  

−7

 

​  

=2.514×10  

−7

  Ωm