Thermodynamics
Thermal Expansion Explained
Why do bridges have gaps, and why is the Eiffel Tower taller in summer? Thermal expansion explained with the ΔL = αL₀ΔT formula, real coefficients, worked examples and an interactive lab.
13 min read
Topic Cluster
Thermodynamics
Thermodynamics: heat, temperature, entropy and energy transfer — the science of engines, refrigerators and the universe’s arrow of time.
What Is Thermodynamics?
Thermodynamics is the physics of heat, temperature and energy transfer in systems made of enormous numbers of particles — where entropy emerges from the statistics of countless tiny collisions.
| Relationship | Equation | What it tells you |
|---|---|---|
| Specific heat | Q = m·c·ΔT | Energy to change a temperature |
| Latent heat | Q = m·L | Energy to change a state |
| First law | ΔU = Q − W | Energy conservation for a gas |
| Ideal gas law | P·V = n·R·T | State of an ideal gas |
| Carnot efficiency | η = 1 − Tc / Th | Best possible heat-engine efficiency |
| Entropy change | ΔS = Q / T | Disorder gained in a reversible step |
