Why in a bimetallic stip it expands when it is heated

Asked by priyabrata.sinhababu | 13th Jun, 2017, 12:00: PM

Expert Answer:

A bimetallic strip is a strip composed of two different metals. Its primary purpose is to convert a temperature change into displacement/movement.
 
It is composed of metals and as we know metals expand on heating. So, a bimetallic strip expands when heated. The purpose of using two metals is to induce different expansions. The metal with a higher rate of expansion is on the outside while the one with a lower rate is on the inside. This setup causes a larger sideways expansion than the usual lengthwise expansion.
 
But, the main part to be understood in this is that metals expand on heating and that is why they are used in a bimetallic strip.

Answered by Romal Bhansali | 13th Jun, 2017, 03:10: PM