Thermal Expansion

Why bridges have gaps

An interactive lesson with 6 steps, about 5 minutes: you predict, drag and solve, with instant feedback on every answer. It runs in your browser and needs JavaScript.

What you’ll learn

• Linear expansion: $\Delta L = \alpha L \Delta T$.
• Structures need gaps or pre-stressing to cope with expansion.
• Water is unusual: densest at 4 °C, and ice floats.

Steps

1. Growing with heat
2. A growing tower
3. Rail gaps
4. Bimetallic strips
5. A growing bridge
6. Water is weird