Table of the Greek alphabet and what the letters are commonly used to designate. Name Capital Small Commonly Used to Designate Alpha A α Angles, coefficients, attenuation constant, absorption factor, area Beta B β Angles, coefficients, phase constant, luminous intensity Gamma Γ γ Complex propagation constant (cap), specific gravity, angles, electrical conductivity, propagation constant, surface tension (small) Delta Δ δ Increment or decrement (cap or small), determinant (cap), permittivity (cap), density, angles Epsilon Ε ε Dielectric constant, permittivity, base of natural logarithms, electric intensity, emissivity Zeta Ζ ζ Coordinates, coefficients Eta Η η Intrinsic impedance, efficiency, surface charge density, hysteresis, coordinates, luminous efficiency Theta Θ θ Angular phase displacement, time constant, reluctance, angles Iota Ι ι Unit vector Kappa Κ κ Susceptibility, coupling coefficient, thermal conductivity Lambda Λ λ Permeance (cap), wavelength, attenuation constant Mu Μ μ Permeability, amplification factor, prefix micro, refractive index Nu Ν ν Reluctivity, frequency, wavelength Xi Ξ ξ Coordinates Omicron Ο ο Pi Π π 3.1416 Rho Ρ ρ Resistivity, volume charge density, coordinates, reflection factor Sigma Σ σ Summation (cap), surface charge density, complex propagation constant, electrical conductivity, leakage coefficient, wavelength, deviation Tau Τ τ Time constant, volume resistivity, time-phase displacement, transmission factor, density Upsilon Υ υ Phi Φ φ Scalar potential (cap), magnetic flux, angles Chi Χ χ Electric susceptibility, angles Psi Ψ ψ Dielectric flux, phase difference, coordinates, angles Omega Ω ω Resistance in ohms (cap), solid angle (cap), angular velocity
