Question

What is resistivity ?

Answer 1

Hint:In order to answer the above question, we will discuss the property of the materials known as resistivity. We will learn the term resistivity in detail and derive its formulae. We will also discuss the resistance of materials such as conductor, insulator and alloy.

Complete answer:
Resistivity is a measurement of a material's resistance to electrical conduction at a given size. Although these terms are less commonly used, resistivity may also be referred to as specific electrical resistance or volume resistivity.While all materials resist the flow of electrical current, some are better than others at conducting it.

The resistivity is a measurement that allows you to compare how different materials permit or resist current flow. Specific units for resistivity are used to make measurements meaningful, and there are formulas for measuring it and comparing it to the resistance in Ohms for a given size of material.

Conductors are materials that quickly conduct electrical current and have a low resistivity. Insulators are materials that are difficult to conduct electricity and have a high resistivity. The resistivity of various materials influences the materials used for electrical wire in many electronic components, such as resistors and integrated circuits. Therefore, we can say that:
Resistivity of conductors < Resistivity of alloys < Resistivity of insulators

The basic electrical resistance of a material specimen is also known as its electrical resistivity.It's a measurement for how well a substance resists the flow of electric current.The $ohm\cdot meter(\Omega )$ is the SI unit for electrical resistivity. The Greek letter rho$(\rho )$ is widely used to describe it. The mathematical equation for resistivity can be given by:
$\rho =\dfrac{R\times A}{L}$
Where, $\rho $ is the resistivity, $R$ is the resistance of the material, $A$ is the cross-sectional area and $L$ is the length. The resistance given by a material per unit length for a unit cross-section is known as resistivity.

Note:It is very important to note that the resistance, resistivity and a resistor, all of the three terms are different from each other. The resistivity is the property of the material to resist the flow of current and is the resistance of a material at unit area and unit length. The resistance is directly proportional to the materials length and inversely proportional to its area, and the constant of proportionality is the resistivity. A resistor is a device which is used in an electrical circuit to provide resistance to it.