Question 1 Report
A bimetallic strip is made of brass and iron. Brass expands more than iron for the same rise in temperature. When the strip is heated it bends as shown. Which metal is on the OUTSIDE of the curve?
The correct answer is D (metal P, because it expands more). When a bimetallic strip is heated, the metal that expands more becomes longer and is forced onto the outside of the curve, while the metal that expands less stays on the inside. In the diagram metal P is on the outside, so it must be the one that expands more.
Saying metal Q expands more contradicts the bending shown, and saying metal P expands less is inconsistent with it being on the longer, outer edge.
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