Question

When a bimetallic strip is heated, it

• A. Does not bend at all
• B. Gets twisted in the form of an helix
• C. Bends in the form of an arc with the more expandable metal outside
• D. Bends in the form of an arc with the more expandable metal inside

Answer 1

The correct option is C

Bends in the form of an arc with the more expandable metal outside

Bimetallic strip:- Two different metal plates of the same size are placed one over the other and they are joined by rivets to make a bimetallic strip at normal temperature.

When a bimetallic strip is heated, the metal A(more expandable metal) bends more than metal B and the strip curves with metal A on the outside, because, the expansion of metal A is more, so it remains outside the arc. And if the strip is cooled, metal B will be on the outside.