When a Metal Ring is Heated, Does the Hole Expand, Contract, or Stay the Same Size?

Spoiler alert: The puzzle is answered in the update at the end of this post. Most solids expand when heated and contract when cooled. Water/ice is anomalous in that it expands when cooled, at least near its freezing point. If you’ve been unfortunate to forget a bottle of water in the freezer, only to find … Read more