When a bimetallic bar made of copper and iron strips is heated, it

The bimetallic strip will bend to the iron's way since

When heated copper expands more than iron

Explanation:

bimetallic strips are temperature regulatory devices used to convert a temperature change into mechanical displacement.

It consists of two layers, usually iron and copper which layers are joined together to form the strip owing to the difference in the constants of expansion of the two materials, a flat strip will bend one way (toward the iron part) if heated. The linear thermal expansion coefficient relates the change in temperature to the change in a material's linear dimensions.