Exploring Thermal Expansion

Middle School Science Fair Project
Photo © 2010 William Warby, Flickr

Ever witnessed how cold winter temperatures can cause the wood in building structures to contract, creating gaps where the wall meets the ceiling, etc? Ever noticed how the intense Florida heat causes roadways to buckle? Both of these phenomena can be explained by thermal expansion and are the subject of this fun physics science project.

Thermal Expansion

Thermal expansion results when matter changes volume in response to a change in temperature - a rise or drop. In most cases, when materials are exposed to high heat, its particles start to move more rapidly, creating a greater average separation and thus causing the material to expand. The opposite is true for those materials that are exposed to lower temperatures.

Project Overview

In this experiment, students will observe the expansion and contraction caused by changes in temperature by creating a heat detector with simple household items - a block of wood, a rubber band, a push pin, and cardboard. NOTE: This project requires the use of matches and should be done only with the assistance of an adult in a safe environment (i.e. no flammable items). For a look into the project procedure, observations, and conclusions check out one or both of the following links: