Thermodynamics & Statistical Physics
7 terms
Temperature
Thermodynamics & Statistical Physics
K (°C, °F)
A macroscopic scalar measure of the average translational kinetic energy of constituent particles in a physical system.
1 / T = (∂S / ∂U)_V, E_avg = (3/2) kB T
Thermal Conduction
Thermodynamics & Statistical Physics
W/m² (k in W/(m·K))
The transfer of thermal energy through a stationary medium via microscopic particle collisions and free electron movement without bulk fluid movement.
q = -k A (dT/dx) (Fourier's Law)
Thermal Convection
Thermodynamics & Statistical Physics
W (h in W/(m²·K))
The transfer of heat energy between a solid surface and an adjacent moving fluid, driven by bulk fluid motion.
q = h A (T_surface - T_fluid) (Newton's Law of Cooling)
Thermal Efficiency
Thermodynamics & Statistical Physics
Dimensionless (%)
The dimensionless ratio of net mechanical work produced by a heat engine to total thermal energy input supplied.
η = W_net / Q_input = 1 - (Q_out / Q_in)
Thermal Radiation
Thermodynamics & Statistical Physics
W
The emission of electromagnetic energy from matter due to thermal agitation of its charged constituent particles.
P = ε σ A T⁴ (Stefan-Boltzmann Law)
Thermal Stress
Thermodynamics & Statistical Physics
Pa (N/m²)
Mechanical stress developed within a material when thermal expansion or contraction is constrained by rigid boundaries.
σ = E α ΔT
Third Law of Thermodynamics
Thermodynamics & Statistical Physics
J/K
The law stating that as system temperature approaches absolute zero (0 K), entropy of a pure crystalline substance approaches a minimum constant value of zero.
lim (T → 0) S = 0