Why does brass expand more in a bimetallic strip if it's on the inside?

[marmot]

Homework Statement

In a bimetallic strip of brass and copper which curls when heated, the brass is on the inside of the curve.

True or false?

Homework Equations

deltaL=alpha*Lo*deltaT

The Attempt at a Solution

It is false but I do not get why. Brass has a higher coefficient of linear expansion so if it is in the inside, I suppose it will expand faster than the copper causing stress in the copper to curl?

 

[Delphi51]

Brass expands more, so the strips will bend so the brass strip is on the outside. If it bent so far as to form a circle, you could say greater radius, greater circumference.