Thermodynamics

Heat required to change temperature of a substance.

Heat required for phase change at constant temperature.

Change in length due to temperature change.

Change in volume due to temperature change.

Rate of heat flow through a material.

Power radiated by a body due to its temperature.

Thermal analog of electrical resistance. ΔT = P × R_th.

Rate of cooling proportional to temperature difference. Solution: T(t) = T_env + (T₀ - T_env)e^(-ht).

Energy conservation: ΔU = Q - W (physics convention).

Work done by expanding gas (area under P-V curve).

Work for isothermal (constant T) expansion of ideal gas.

Internal energy depends only on temperature for ideal gas.

Relationship for adiabatic (no heat transfer) process. Also: T₁V₁^(γ-1) = T₂V₂^(γ-1).

Mayer relation: C_p is always greater than C_v by R for ideal gases.

Work done during adiabatic expansion or compression.

Heat content at constant pressure. ΔH = Q_p for constant pressure processes.

Entropy change for reversible isothermal process.

Maximum efficiency of heat engine between two temperatures.

Efficiency of any heat engine.

Performance metric for refrigerators.

Performance metric for heat pumps. COP_HP = COP_R + 1.

Entropy change is at least Q/T. Equality holds for reversible processes.

Equation of state for ideal gas.

Ideal gas law in terms of molecules.

Average translational KE of gas molecule.

RMS speed of gas molecules.

Average distance a molecule travels between collisions.

Pressure from molecular collisions. Connects microscopic motion to macroscopic pressure.

Speed at which Maxwell-Boltzmann distribution peaks.

Average speed of gas molecules from Maxwell-Boltzmann distribution.

Entropy change for ideal gas between two states.

Statistical definition of entropy.

Maximum non-expansion work at constant T and P. ΔG < 0 for spontaneous processes.

Maximum work extractable at constant T and V. Also denoted A.