Suppose there are two circuit. Both have same watt bulb and same volt battery. Diffrence between two circuit is only that one circuit is made up of copper wire and another is of iron wire. As we all know copper is good conductor than iron. Does this factor effect the brightness of bulb or something other is affected?
-
The material you use to make the wire will almost certainly have an effect on the brightness of the bulb. This goes back to Ohm's Law which states, Voltage = Current x Resistance. If a material has a higher resistance then (for a given voltage) less current will flow through the circuit. This also means that there will be less power dissipated by the bulb (i.e. the bulb will be less bright). This is why it is very important for the wires to be very good conductors so power isn't wasted in the wires heating.
-
The wire type certainly does have effect on the overall current flow because it however small does present an added resistance. But there are also real world considerations; especially with iron, because of corrosion and size change due to heat. There was a period when aluminum wire was tried but became unpopular because the connections had to be retightened frequently.