Question

A bimetallic strip is made of iron and brass; when heated in a flame :

• A. the iron expands more than brass
• B. the brass expands more than iron
• C. both iron and brass expand equal
• D. none of these

Answer 1

The correct option is B the brass expands more than iron

Both the strips will expand in proportion to their linear thermal coefficients of expansion.

Coefficient of linear expansion of brass and iron are $19\times {10}^{-6}{C}^{-1}$ and $12\times {10}^{-6}{C}^{-1}$ respectively. Hence, brass expands more than iron.