Q. Why is constantan wire used for making rheostat?

A
High specific resistance
B
Less change in resistance with temperature variations
C
Ease of availability
D
It is a cheap alloy
Solution:

Constantan is a copper?nickel alloy also known as Eureka, Advance, and Ferry. It usually consists of 55% copper and 45% nickel. Its main feature is its resistivity, which is constant over a wide range of temperatures. Other alloys with similarly low temperature coefficients are known, such as manganin.

Entri Contact Image

Get Expert Advice for Free: Register for Your Free Consultation Now!