Question

If brass and iron strips are used in bimetallic thermometer , which will expand more when the temperature rises ? How would the bimetallic strip bend?

Answer 1

The coefiicient of linear expansion for brass is
$18.7\times {10}^{-6}\raisebox{1ex}{$m$}\!\left/ \!\raisebox{-1ex}{$m-K$}\right.andthatforironis10.8\times {10}^{-6}\raisebox{1ex}{$m$}\!\left/ \!\raisebox{-1ex}{$m-K$}\right..$
So, when the strip is heated brass will expand more and it will bend outwards.