Why Does a Bimetallic Strip Bend When Heated?

[Saladsamurai]

I have this multiple choice question:

Two thin strips of iron and zinc are riveted together to form a bimetallic strip that bends when heated. The iron is on the inside of the bend because:


(A) it has a higher coefficient of linear expansion
(B) it has a lower coefficient of linear expansion
(C)it has a lower specific heat
(D)it conducts heat better

Here is a poor "side-view" diagram of the scenario.
zinc--->((<----iron

I am going with B. Since the iron has a lower coeff. of linear expansion, it does not expand as 'willingly' as the zinc and thus 'holds' it down actually causing the bend rather than the zinc actually expanding.

This my reasoning. Am I correct in thinking this?

Casey

 

[rl.bhat]

Yes. You are right.