Question

State three characteristics of the material which make it useful for making heating elements of electric devices.

Name two such materials used industrially.

Answer 1

Three characteristics of the material which make it useful for making heating elements of electric devices are explained below:

1. The material of the element should have a high melting point so that it does not melt at a high temperature.
2. The resistivity of the element should be very high so that more and more heat is generated.
3. The temperature coefficient of resistance should be very low so that it heats gradually and up to a high temperature.

Two materials that are used industrially are explained below:

1. Nichrome: Most resistance wire heating elements usually use nichrome $(80\%Nickel,20\%Chromium)$ wire.
2. Cupronickel $\left(\mathrm{CuNi}\right)$ alloys for low-temperature heating