ΔL = α·L₀·ΔT area ΔA ≈ 2α·A₀·ΔT · volume ΔV ≈ 3α·V₀·ΔT

Thermal Expansion: How materials grow when heated. This free calculator solves for Length/area/volume change and shows every step.

The physics

Most materials expand when heated because their atoms vibrate more vigorously and sit farther apart on average. Area expands at roughly twice, and volume at roughly three times, the linear rate.

Worked example

A 10 m steel beam warmed by ΔT = 30 °C. ΔL = 12 × 10⁻⁶ · 10 · 30 = 0.0036 m = 3.6 mm — small, but enough to require expansion joints.

Common uses

Bridge and railway expansion joints, pipeline design, bimetallic-strip thermostats, precision instruments, glass-to-metal seals.

Frequently asked questions

What is the formula for Thermal Expansion?

Thermal Expansion uses the formula ΔL = α·L₀·ΔT. How materials grow when heated.

How do you calculate Thermal Expansion?

Choose which variable to solve for, enter the values you know (in any supported unit), and the calculator substitutes them into ΔL = α·L₀·ΔT and shows every step of the working. It can solve for Length/area/volume change.

Is the Thermal Expansion calculator free to use?

Yes — every Physics Fundamentals calculator is completely free, with no login, no ads and no usage limits.