Physics, asked by JAINISH3661, 1 year ago

Why alloys like constantan or manganin are used for making standard resistors?

Answers

Answered by JinKazama1
0
Alloys like constantan (Cu-Ni ) or Manganin (Cu-Mn-Ni) are used for making standard resistors due to following reason :

1) LOW THERMAL COEFFICIENT OF RESISTANCE :

=>As we know. dealing with electricity also involves heat generation,which in turn increases the temperature of electrical equipment.

=> But, we never want to make changes to the physical units of that equipment.
Here in this case, With increases in temperature, we will not like to change the resistance of equipment.

Therefore, those equipments are made up of alloys which have LOW THERMAL COEFFI CIENT OF RESISTANCE.

=> Their resistance almost remains constant on varying temperature.

=> Their Thermal coefficient of resistance are about 100 times lower than other known materials.
Therefore, they are selected in this race.


2) HIGH RESISTIVITY :
Trivial :
On changing dimension of the equipment, it's resistance doesnt vary much she to their high resistivity.


Similar questions