Question

Define resistivity of material

Answer 1

The resistivity of a material is the resistance of a wire of that material of unitlength and unit cross-sectional area. The unit for resistivity is the ohm-metre.The resistivity of a material depends on itsnature and the temperature of the conductor, but not on its shape and size.A good conductor has less resistivity, whereas a bad conductor or insulator has high resistivity.The resistivity of semi-conductors lies between that of conductors and insulators. The resistivity of a metallic conductor increases with an increase in its temperature, whereas the resistivity of a semi-conductor decreases with an increase in its temperature.

Answer 2

Hey mate..
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What is resistivity ?

>> Resistivity is the ability of a material to resist the flow of current.

>> If the resistivity of the material is more, it will allow less current to pass through it

>> But, if the resistivity of the material is less, it will allow current more to pass through it.

>> We can say that insulting materials like Glass, rubber, Paper etc have more resistivity so they don't allow sufficient current to flow through them.

>> We can also say that conducting materials like Silver , Copper , Iron etc will have less resistivity so they do allow sufficient current to flow through them.

In mathematical expression, we have,

R $\alpha$ L / A

R = P L/A

In this, P (rho) is a constant of proportionality and is called electrical resistivity of the material of the conductor.

Whereas, L is the length, A is the area and R is the resistance provided.

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