Thermal Physics · Physics

Expansion is predictable—until constraints create stress.

Model how length and volume change with temperature, and learn what happens when expansion is prevented.

This topic

Thermal Expansion

Use expansion coefficients for simple estimates, then connect constrained expansion to thermal stress.

Core model

Linear expansion

For small temperature changes, length change is proportional to initial length and temperature change.

Geometry

Area and volume expansion

Area and volume expansion follow from linear expansion when the material expands isotropically.

Constraints

Thermal stress and constrained expansion

If an object cannot expand freely, internal forces appear. Thermal strain becomes mechanical stress.

Applications

Real-world effects

Expansion shows up everywhere: bridges, rails, pipes, glassware, and temperature-sensitive instruments.

Practice

Practice & Exercises

Practice coefficient-based computations and qualitative reasoning about constraints and stress.