Linear Thermal Expansion Formula — the NEET Physics formula with its derivation, variables, validity constraints and worked solver.
Linear Thermal Expansion Formula Valid for isotropic solids undergoing small temperature changes where alpha can be considered constant. Assume change in length dL is proportional to initial length L0 Assume change in length dL is proportional to change in temperature dT Combine proportionalities: dL ∝ L0 dT Introduce constant of proportionality alpha Material is isotropic Temperature change is not large enough to change phase or significantly alter alpha Pressure remains constant (usually ignored for solids) Thinking alpha is the same for area and volume expansion (Area is approx 2 alpha, Volume approx 3 alpha) Believing holes in a material shrink when heated (they expand as if filled with material) Confusing Celsius change with Kelvin change (magnitude is identical)