Why is it that some wires get hot,having electricity flow throught them,while others don't?And why is it that when there is a lot of resistance in a wire, that it doesn't get hot?Why does the length of a wire has an effect on the temperature of that wire, and how exactly?
we know that the power = i^2 *r where i : is the current through the wire. r : is the equivalent resistance of the current. so this power will be consumed in the wire in form of heat, so if the resistance of any wire increase, the absorbed power will increase. Also we know the resistance of any wire = * l / a where : - = constant, the resistivity of the matter ( copper, aluminum,... ). - l = the length of the wire. - a = cross section of area of the wire. as the length of the wire increase, the resistance will increase, so the power will increase, this lead to increase of the heat in the wire.
Well it depends. If you varry the current the temperature of the wire will also vary. You have to take into account the actual diameter of the wire, the wider the wire, and constant current, the cooler the wire will be when you run electricity through it. If you have a wire with HIGH resistance it will get HOTTER, thats how light bulbs work.
The temperature of a conductor(wire) is directly proportional to the resistance of the conductor and directly proportional to the current flowing through the wire. high resistance and high current high temperature high resistance and low current lower temperature low resistance and high current lower temperature A cool wire with low temperature either doesn't have a current through it or very low current The longer a given wire the higher the resistance( see number one answer)
