Question

A wire is 1m long ,0.2mm in diameter and has resistance of 10ohm . Calculate its resistivity

Answer 1

Hi friend

Here is your answer -:

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Here, it's given that

l=1m, d=0.2mm=>r=0.1mm and R = 10 ohm

by using the formula,

R= p౹/ A

= p౹/ πr²

therefore, p= Rπr²/l

= 10× 3.14×( 0.1× 10 -³)²

= 10× 3.14× 0.1×0.1× 10 to the power -6

= 0.314× 10 to the power-6

= 3.14× 10 to the power-7 ohm- m

hence, the resistivity of the conductor is 3.14× 10 to the power-7 ohm- m


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Hope it helps :)

Answer 2

Hey there!

Given,

Length(l) = 1 m

Diameter(d) = 0.2 mm

Radius(r) = 0.1 mm or 0.001 m

Resistance(R) = 10 Ω

Now,

 Area =πr²

         = 3.14 × 0.001 × 0.001

         = 0.00000314 m²

We know,

Resistivity = RA/l

                = 10 × 0.00000314/1

                = 0.0000314 Ω m

                = 3.14×10^-7 Ω m

Hope It Helps You!