Thermodynamics is about heat: what a temperature change costs in energy, and how matter reacts to it. Q = mcΔT gives the energy needed to warm a mass by a number of degrees, the expansion coefficient α says how much a material grows per degree (ΔL = αL₀ΔT), and the ideal gas law (pV = nRT) ties a gas's pressure, volume and temperature into one equation.
Calculate the heat energy needed to change a substance's temperature (Q = mcΔT).
Q = m × c × ΔTCalculate how much a material lengthens when heated (linear thermal expansion, ΔL = αL₀ΔT).
ΔL = α × L₀ × ΔTSolve the ideal gas law PV = nRT for pressure from amount, temperature and volume.
P = n·R·T / VThese come up whenever heat carries a price or a consequence — heating a tank of water, leaving an expansion gap in a pipe or a rail, or working out what a sealed gas cylinder does as the day warms up. The specific-heat calculator assumes no phase change (nothing melting or boiling) and a constant specific heat across the range; the ideal gas law is an approximation that holds well for dilute gases far from condensing, and needs absolute temperature in kelvin.