Question

conductivity is dependent upon temperature. Given this, is it safe to say that a metallic wire is an ohmic element?

Why or why not?

Answer 1

Basically conductivity is material's ability to conduct electric current and is defined as the reciprocal of resistivity so higher the conductivity of a wire higher its electrical passage ability or lesser the resistance offered.

Now when we consider a metallic wire , it consists of single core of multiple core wire and when a potential difference is applied across its ends current starts flowing through the wire. During the phenomenon of flowing current through metallic wire some resistance is offered by such wire depending upon the type of metallic wire i have taken and that resistance depends totally upon the physical properties like temperature, lenght, cross section area of the metallic wire not upon the voltage and current we are supplied to it. So when electricity starts flow through the metallic wire some heat is generated by the wire due to the motion of electron through it and that heat indicates the losses of energy. Now ohmic elements are those elements which shwos the linear relationship between the current and voltage when subjected to the application in general purposes. In case of metallic wire it is quite obvious to say that when we applying the voltage difference across its ends current starts flowing through it and that can be ploted on the graph. When the graph is formed by taking certain values we can clearly see that a linear graph will be obtained and when we extract its slope what we get is the resistance of the metallic wire hence it is safe to say that metallic wire is an ohmic element.

Also temperature dependency of that metallic wire is taken into consideration becasue resistant changes with the change in temperature of that metallic wire or for every wire. In fact resistance is such a parameter which cannot be find absolutely without the knowledge of temperature at particular point where we have to know the resistance of that wire.