The alloys constantan and manganin are used to make standard resistance due to they have?
Hint:Let us first understand about alloy. A metal admixture, or a metal mixed with one or more other components, is known as an alloy. Combining the metals gold and copper, for example, yields red gold, gold and silver yields white gold, and silver mixed with copper yields sterling silver.
Complete answer: Let us understand about Constantan alloy first. The copper–nickel alloy known as Eureka, Advance, and Ferry is also known as Constantan. It typically has a copper content of \[55\] percent and a nickel content of \[45\] percent. Its key distinguishing feature is its low thermal variance of resistivity, which remains constant over a large temperature range.
Now let us get some idea about Manganin alloy. Manganin is a trademarked term for a copper-manganese-nickel alloy with an average composition of \[84.2\] percent copper,\[12.1\] percent manganese, and \[3.7\] percent nickel. Edward Weston created it in \[1892\] as an improvement on his Constantan. Manganin foil and wire are used in the production of resistors, especially ammeter shunts, due to its low temperature coefficient of resistance and long-term stability.
Now, The high resistivity, low temperature coefficient of resistance, ability to achieve good resistance values in small sizes, reliability, and ability to draw in thin wires all contribute to Constantan preference for resistance wire. It has a melting point of over \[1200\] degrees Celsius. Manganin wire is used to make normal resistances because of its high resistivity and low temperature coefficient of resistance.
Note:Because of its many unique characteristics, Constantan is considered as the most flexible alloy available. Pure aluminium is a relatively soft metal and pure copper is also quite soft. However, when aluminium is alloyed with copper, the resulting alloy’s strength is far greater than that of its parent metals.