Question

The standard resistance coils r made of managing. Why.??

Answer 1

Resitance is that property of conductor which oppose the flow of electric current in any conductor..
Or simply we can say Resistance is an opposition to current...the cause of this opposition is Collisions of charges

More collision leads to High resitance and vice versa...When we have increase the temperature..Thermal motion inside the conductor increases due to which collision increases and resitance become high...

So temperature affect the resistance...but in Magnene wire if we increase temp its resistance doesnt changes...so in laboratory we use magnene...