# Formula Symbols - E

Written by Jerry Ratzlaff on . Posted in Nomenclature & Symbols for Engineering, Mathematics, and Science

SymbolGreek SymbolDefinitionUSMetric
$$g$$ - earth (mean) $$ft/sec^2$$ $$m/s^2$$
$$e$$ - eccentricity in mm
$$Ec$$ - Eckert number dimensionless number dimensionless number
$$E$$ - effectiveness - -
$$\xi$$ xi effectiveness - -
$$\eta$$ eta efficiency $$percent$$ $$percent$$
$$E$$ - elasticity - -
$$El$$ - elasticity number dimensionless number dimensionless number
$$q$$ - electric charge - -
$$\phi$$ phi electric potential - -
$$\sigma$$ sigma electrical conductivity - -
$$R_e$$ - electrical resistance $$\Omega$$ $$\Omega$$
$$\rho$$ rho electrical resistivity $$\Omega^{-in}$$ $$\Omega^{-cm}$$
$$e$$ - electron - -
$$F_e$$ - electrostatic force - -
$$y$$ - elevation $$ft$$ $$m$$
$$\gamma$$ gamma empirical constant $$1/^\circ F$$ $$1/K$$
$$r$$ - empirical rate - -
$$E$$ - energy in-lbf J
$$h$$ - enthalpy $$Btu/lbm$$ $$kJ/kg$$
$$s$$ - entropy $$Btu/lbm-^\circ R$$ $$kJ/kg\cdot K$$
$$\Delta S$$ delta entropy differential $$Btu/lbm-^\circ R$$ $$kJ/kg\cdot K$$
$$\phi$$ phi entropy function $$Btu/lbm ^\circ R$$ $$kJ/kg \cdot K$$
$$EW$$ - equivalent weight $$lbm/lbmol$$ $$kg/kmol$$
$$Er$$ - Ericksen number dimensionless number dimensionless number
$$Eu$$ - Euler number dimensionless number dimensionless number
$$Y$$ - expansion factor - -