Glossary of Key Symbols and Notation
In this glossary, key symbols and notation are briefly defined.
| Symbol | Definition |
|---|---|
| [latex]\overline{\text{any symbol}}[/latex] | average (indicated by a bar over a symbol—e.g., [latex]\overline{v}[/latex] is average velocity) |
| [latex]°\text{C}[/latex] | Celsius degree |
| [latex]°\text{F}[/latex] | Fahrenheit degree |
| [latex]\text{//}[/latex] | parallel |
| [latex]\perp[/latex] | perpendicular |
| [latex]\propto[/latex] | proportional to |
| [latex]±[/latex] | plus or minus |
| [latex]{\phantom{\rule{0.25em}{0ex}}}_{0}[/latex] | zero as a subscript denotes an initial value |
| [latex]\alpha[/latex] | alpha rays |
| [latex]\alpha[/latex] | angular acceleration |
| [latex]\alpha[/latex] | temperature coefficient(s) of resistivity |
| [latex]\beta[/latex] | beta rays |
| [latex]\beta[/latex] | sound level |
| [latex]\beta[/latex] | volume coefficient of expansion |
| [latex]{\beta }^{-}[/latex] | electron emitted in nuclear beta decay |
| [latex]{\beta }^{+}[/latex] | positron decay |
| [latex]\gamma[/latex] | gamma rays |
| [latex]\gamma[/latex] | surface tension |
| [latex]\gamma =1/\sqrt{1-{v}^{2}/{c}^{2}}[/latex] | a constant used in relativity |
| [latex]\Delta[/latex] | change in whatever quantity follows |
| [latex]\delta[/latex] | uncertainty in whatever quantity follows |
| [latex]\mathrm{\Delta E}[/latex] | change in energy between the initial and final orbits of an electron in an atom |
| [latex]\mathrm{\Delta E}[/latex] | uncertainty in energy |
| [latex]\mathrm{\Delta m}[/latex] | difference in mass between initial and final products |
| [latex]\mathrm{\Delta N}[/latex] | number of decays that occur |
| [latex]\mathrm{\Delta p}[/latex] | change in momentum |
| [latex]\mathrm{\Delta p}[/latex] | uncertainty in momentum |
| [latex]\Delta {\text{PE}}_{\text{g}}[/latex] | change in gravitational potential energy |
| [latex]\mathrm{\Delta \theta }[/latex] | rotation angle |
| [latex]\mathrm{\Delta s}[/latex] | distance traveled along a circular path |
| [latex]\mathrm{\Delta t}[/latex] | uncertainty in time |
| [latex]{\mathrm{\Delta t}}_{0}[/latex] | proper time as measured by an observer at rest relative to the process |
| [latex]\mathrm{\Delta V}[/latex] | potential difference |
| [latex]\mathrm{\Delta x}[/latex] | uncertainty in position |
| [latex]{\epsilon }_{0}[/latex] | permittivity of free space |
| [latex]\eta[/latex] | viscosity |
| [latex]\theta[/latex] | angle between the force vector and the displacement vector |
| [latex]\theta[/latex] | angle between two lines |
| [latex]\theta[/latex] | contact angle |
| [latex]\theta[/latex] | direction of the resultant |
| [latex]{\theta }_{b}[/latex] | Brewster’s angle |
| [latex]{\theta }_{c}[/latex] | critical angle |
| [latex]\kappa[/latex] | dielectric constant |
| [latex]\lambda[/latex] | decay constant of a nuclide |
| [latex]\lambda[/latex] | wavelength |
| [latex]{\lambda }_{n}[/latex] | wavelength in a medium |
| [latex]{\mu }_{0}[/latex] | permeability of free space |
| [latex]{\mu }_{\text{k}}[/latex] | coefficient of kinetic friction |
| [latex]{\mu }_{\text{s}}[/latex] | coefficient of static friction |
| [latex]{v}_{e}[/latex] | electron neutrino |
| [latex]{\pi }^{+}[/latex] | positive pion |
| [latex]{\pi }^{-}[/latex] | negative pion |
| [latex]{\pi }^{0}[/latex] | neutral pion |
| [latex]\rho[/latex] | density |
| [latex]{\rho }_{\text{c}}[/latex] | critical density, the density needed to just halt universal expansion |
| [latex]{\rho }_{\text{fl}}[/latex] | fluid density |
| [latex]{\overline{\rho }}_{\text{obj}}[/latex] | average density of an object |
| [latex]\rho /{\rho }_{\text{w}}[/latex] | specific gravity |
| [latex]\tau[/latex] | characteristic time constant for a resistance and inductance [latex]\left(\text{RL}\right)[/latex] or resistance and capacitance [latex]\left(\text{RC}\right)[/latex] circuit |
| [latex]\tau[/latex] | characteristic time for a resistor and capacitor [latex]\left(\text{RC}\right)[/latex] circuit |
| [latex]\tau[/latex] | torque |
| [latex]Υ[/latex] | upsilon meson |
| [latex]\Phi[/latex] | magnetic flux |
| [latex]\varphi[/latex] | phase angle |
| [latex]\Omega[/latex] | ohm (unit) |
| [latex]\omega[/latex] | angular velocity |
| [latex]A[/latex] | ampere (current unit) |
| [latex]A[/latex] | area |
| [latex]A[/latex] | cross-sectional area |
| [latex]A[/latex] | total number of nucleons |
| [latex]a[/latex] | acceleration |
| [latex]{a}_{\text{B}}[/latex] | Bohr radius |
| [latex]{a}_{\text{c}}[/latex] | centripetal acceleration |
| [latex]{a}_{\text{t}}[/latex] | tangential acceleration |
| [latex]\text{AC}[/latex] | alternating current |
| [latex]\text{AM}[/latex] | amplitude modulation |
| [latex]\text{atm}[/latex] | atmosphere |
| [latex]B[/latex] | baryon number |
| [latex]B[/latex] | blue quark color |
| [latex]\overline{B}[/latex] | antiblue (yellow) antiquark color |
| [latex]b[/latex] | quark flavor bottom or beauty |
| [latex]B[/latex] | bulk modulus |
| [latex]B[/latex] | magnetic field strength |
| [latex]{\text{B}}_{\text{int}}[/latex] | electron’s intrinsic magnetic field |
| [latex]{\text{B}}_{\text{orb}}[/latex] | orbital magnetic field |
| [latex]\text{BE}[/latex] | binding energy of a nucleus—it is the energy required to completely disassemble it into separate protons and neutrons |
| [latex]\text{BE}/A[/latex] | binding energy per nucleon |
| [latex]\text{Bq}[/latex] | becquerel—one decay per second |
| [latex]C[/latex] | capacitance (amount of charge stored per volt) |
| [latex]C[/latex] | coulomb (a fundamental SI unit of charge) |
| [latex]{C}_{\text{p}}[/latex] | total capacitance in parallel |
| [latex]{C}_{\text{s}}[/latex] | total capacitance in series |
| [latex]\text{CG}[/latex] | center of gravity |
| [latex]\text{CM}[/latex] | center of mass |
| [latex]c[/latex] | quark flavor charm |
| [latex]c[/latex] | specific heat |
| [latex]c[/latex] | speed of light |
| [latex]\text{Cal}[/latex] | kilocalorie |
| [latex]\text{cal}[/latex] | calorie |
| [latex]{\text{COP}}_{\text{hp}}[/latex] | heat pump’s coefficient of performance |
| [latex]{\text{COP}}_{\text{ref}}[/latex] | coefficient of performance for refrigerators and air conditioners |
| [latex]\text{cos}\phantom{\rule{0.20em}{0ex}}\theta[/latex] | cosine |
| [latex]\text{cot}\phantom{\rule{0.20em}{0ex}}\theta[/latex] | cotangent |
| [latex]\text{csc}\phantom{\rule{0.20em}{0ex}}\theta[/latex] | cosecant |
| [latex]D[/latex] | diffusion constant |
| [latex]d[/latex] | displacement |
| [latex]d[/latex] | quark flavor down |
| [latex]\text{dB}[/latex] | decibel |
| [latex]{d}_{\text{i}}[/latex] | distance of an image from the center of a lens |
| [latex]{d}_{\text{o}}[/latex] | distance of an object from the center of a lens |
| [latex]\text{DC}[/latex] | direct current |
| [latex]E[/latex] | electric field strength |
| [latex]\epsilon[/latex] | emf (voltage) or Hall electromotive force |
| [latex]\text{emf}[/latex] | electromotive force |
| [latex]E[/latex] | energy of a single photon |
| [latex]E[/latex] | nuclear reaction energy |
| [latex]E[/latex] | relativistic total energy |
| [latex]E[/latex] | total energy |
| [latex]{E}_{0}[/latex] | ground state energy for hydrogen |
| [latex]{E}_{0}[/latex] | rest energy |
| [latex]\text{EC}[/latex] | electron capture |
| [latex]{E}_{\text{cap}}[/latex] | energy stored in a capacitor |
| [latex]\text{Eff}[/latex] | efficiency—the useful work output divided by the energy input |
| [latex]{\text{Eff}}_{\text{C}}[/latex] | Carnot efficiency |
| [latex]{E}_{\text{in}}[/latex] | energy consumed (food digested in humans) |
| [latex]{E}_{\text{ind}}[/latex] | energy stored in an inductor |
| [latex]{E}_{\text{out}}[/latex] | energy output |
| [latex]e[/latex] | emissivity of an object |
| [latex]{e}^{+}[/latex] | antielectron or positron |
| [latex]\text{eV}[/latex] | electron volt |
| [latex]\text{F}[/latex] | farad (unit of capacitance, a coulomb per volt) |
| [latex]\text{F}[/latex] | focal point of a lens |
| [latex]\mathbf{\text{F}}[/latex] | force |
| [latex]F[/latex] | magnitude of a force |
| [latex]F[/latex] | restoring force |
| [latex]{F}_{\text{B}}[/latex] | buoyant force |
| [latex]{F}_{\text{c}}[/latex] | centripetal force |
| [latex]{F}_{\text{i}}[/latex] | force input |
| [latex]{\mathbf{\text{F}}}_{\text{net}}[/latex] | net force |
| [latex]{F}_{\text{o}}[/latex] | force output |
| [latex]\text{FM}[/latex] | frequency modulation |
| [latex]f[/latex] | focal length |
| [latex]f[/latex] | frequency |
| [latex]{f}_{0}[/latex] | resonant frequency of a resistance, inductance, and capacitance [latex]\left(\text{RLC}\right)[/latex] series circuit |
| [latex]{f}_{0}[/latex] | threshold frequency for a particular material (photoelectric effect) |
| [latex]{f}_{1}[/latex] | fundamental |
| [latex]{f}_{2}[/latex] | first overtone |
| [latex]{f}_{3}[/latex] | second overtone |
| [latex]{f}_{\text{B}}[/latex] | beat frequency |
| [latex]{f}_{\text{k}}[/latex] | magnitude of kinetic friction |
| [latex]{f}_{\text{s}}[/latex] | magnitude of static friction |
| [latex]G[/latex] | gravitational constant |
| [latex]G[/latex] | green quark color |
| [latex]\overline{G}[/latex] | antigreen (magenta) antiquark color |
| [latex]g[/latex] | acceleration due to gravity |
| [latex]g[/latex] | gluons (carrier particles for strong nuclear force) |
| [latex]h[/latex] | change in vertical position |
| [latex]h[/latex] | height above some reference point |
| [latex]h[/latex] | maximum height of a projectile |
| [latex]h[/latex] | Planck’s constant |
| [latex]\text{hf}[/latex] | photon energy |
| [latex]{h}_{\text{i}}[/latex] | height of the image |
| [latex]{h}_{\text{o}}[/latex] | height of the object |
| [latex]I[/latex] | electric current |
| [latex]I[/latex] | intensity |
| [latex]I[/latex] | intensity of a transmitted wave |
| [latex]I[/latex] | moment of inertia (also called rotational inertia) |
| [latex]{I}_{0}[/latex] | intensity of a polarized wave before passing through a filter |
| [latex]{I}_{\text{ave}}[/latex] | average intensity for a continuous sinusoidal electromagnetic wave |
| [latex]{I}_{\text{rms}}[/latex] | average current |
| [latex]\text{J}[/latex] | joule |
| [latex]J/\text{Ψ}[/latex] | Joules/psi meson |
| [latex]\text{K}[/latex] | kelvin |
| [latex]k[/latex] | Boltzmann constant |
| [latex]k[/latex] | force constant of a spring |
| [latex]{K}_{\alpha }[/latex] | x rays created when an electron falls into an [latex]n=1[/latex] shell vacancy from the [latex]n=3[/latex] shell |
| [latex]{K}_{\beta }[/latex] | x rays created when an electron falls into an [latex]n=2[/latex] shell vacancy from the [latex]n=3[/latex] shell |
| [latex]\text{kcal}[/latex] | kilocalorie |
| [latex]\text{KE}[/latex] | translational kinetic energy |
| [latex]\text{KE}+\text{PE}[/latex] | mechanical energy |
| [latex]{\text{KE}}_{e}[/latex] | kinetic energy of an ejected electron |
| [latex]{\text{KE}}_{\text{rel}}[/latex] | relativistic kinetic energy |
| [latex]{\text{KE}}_{\text{rot}}[/latex] | rotational kinetic energy |
| [latex]\overline{\text{KE}}[/latex] | thermal energy |
| [latex]\text{kg}[/latex] | kilogram (a fundamental SI unit of mass) |
| [latex]L[/latex] | angular momentum |
| [latex]\text{L}[/latex] | liter |
| [latex]L[/latex] | magnitude of angular momentum |
| [latex]L[/latex] | self-inductance |
| [latex]\ell[/latex] | angular momentum quantum number |
| [latex]{L}_{\alpha }[/latex] | x rays created when an electron falls into an [latex]n=2[/latex] shell from the [latex]n=3[/latex] shell |
| [latex]{L}_{e}[/latex] | electron total family number |
| [latex]{L}_{\mu }[/latex] | muon family total number |
| [latex]{L}_{\tau }[/latex] | tau family total number |
| [latex]{L}_{\text{f}}[/latex] | heat of fusion |
| [latex]{L}_{\text{f}}\phantom{\rule{0.20em}{0ex}}\text{and}\phantom{\rule{0.20em}{0ex}}{L}_{\text{v}}[/latex] | latent heat coefficients |
| [latex]{\text{L}}_{\text{orb}}[/latex] | orbital angular momentum |
| [latex]{L}_{\text{s}}[/latex] | heat of sublimation |
| [latex]{L}_{\text{v}}[/latex] | heat of vaporization |
| [latex]{L}_{z}[/latex] | z – component of the angular momentum |
| [latex]M[/latex] | angular magnification |
| [latex]M[/latex] | mutual inductance |
| [latex]\text{m}[/latex] | indicates metastable state |
| [latex]m[/latex] | magnification |
| [latex]m[/latex] | mass |
| [latex]m[/latex] | mass of an object as measured by a person at rest relative to the object |
| [latex]\text{m}[/latex] | meter (a fundamental SI unit of length) |
| [latex]m[/latex] | order of interference |
| [latex]m[/latex] | overall magnification (product of the individual magnifications) |
| [latex]m\left({\text{}}^{A}\text{X}\right)[/latex] | atomic mass of a nuclide |
| [latex]\text{MA}[/latex] | mechanical advantage |
| [latex]{m}_{\text{e}}[/latex] | magnification of the eyepiece |
| [latex]{m}_{e}[/latex] | mass of the electron |
| [latex]{m}_{\ell }[/latex] | angular momentum projection quantum number |
| [latex]{m}_{n}[/latex] | mass of a neutron |
| [latex]{m}_{\text{o}}[/latex] | magnification of the objective lens |
| [latex]\text{mol}[/latex] | mole |
| [latex]{m}_{p}[/latex] | mass of a proton |
| [latex]{m}_{\text{s}}[/latex] | spin projection quantum number |
| [latex]N[/latex] | magnitude of the normal force |
| [latex]\text{N}[/latex] | newton |
| [latex]\mathbf{\text{N}}[/latex] | normal force |
| [latex]N[/latex] | number of neutrons |
| [latex]n[/latex] | index of refraction |
| [latex]n[/latex] | number of free charges per unit volume |
| [latex]{N}_{\text{A}}[/latex] | Avogadro’s number |
| [latex]{N}_{\text{r}}[/latex] | Reynolds number |
| [latex]\text{N}\cdot \text{m}[/latex] | newton-meter (work-energy unit) |
| [latex]\text{N}\cdot \text{m}[/latex] | newtons times meters (SI unit of torque) |
| [latex]\text{OE}[/latex] | other energy |
| [latex]P[/latex] | power |
| [latex]P[/latex] | power of a lens |
| [latex]P[/latex] | pressure |
| [latex]\mathbf{\text{p}}[/latex] | momentum |
| [latex]p[/latex] | momentum magnitude |
| [latex]p[/latex] | relativistic momentum |
| [latex]{\mathbf{\text{p}}}_{\text{tot}}[/latex] | total momentum |
| [latex]{\mathbf{\text{p}}}_{\text{tot}}^{\text{'}}[/latex] | total momentum some time later |
| [latex]{P}_{\text{abs}}[/latex] | absolute pressure |
| [latex]{P}_{\text{atm}}[/latex] | atmospheric pressure |
| [latex]{P}_{\text{atm}}[/latex] | standard atmospheric pressure |
| [latex]\text{PE}[/latex] | potential energy |
| [latex]{\text{PE}}_{\text{el}}[/latex] | elastic potential energy |
| [latex]{\text{PE}}_{\text{elec}}[/latex] | electric potential energy |
| [latex]{\text{PE}}_{\text{s}}[/latex] | potential energy of a spring |
| [latex]{P}_{\text{g}}[/latex] | gauge pressure |
| [latex]{P}_{\text{in}}[/latex] | power consumption or input |
| [latex]{P}_{\text{out}}[/latex] | useful power output going into useful work or a desired, form of energy |
| [latex]Q[/latex] | latent heat |
| [latex]Q[/latex] | net heat transferred into a system |
| [latex]Q[/latex] | flow rate—volume per unit time flowing past a point |
| [latex]+Q[/latex] | positive charge |
| [latex]-Q[/latex] | negative charge |
| [latex]q[/latex] | electron charge |
| [latex]{q}_{p}[/latex] | charge of a proton |
| [latex]q[/latex] | test charge |
| [latex]\text{QF}[/latex] | quality factor |
| [latex]R[/latex] | activity, the rate of decay |
| [latex]R[/latex] | radius of curvature of a spherical mirror |
| [latex]R[/latex] | red quark color |
| [latex]\overline{R}[/latex] | antired (cyan) quark color |
| [latex]R[/latex] | resistance |
| [latex]\text{R}[/latex] | resultant or total displacement |
| [latex]R[/latex] | Rydberg constant |
| [latex]R[/latex] | universal gas constant |
| [latex]r[/latex] | distance from pivot point to the point where a force is applied |
| [latex]r[/latex] | internal resistance |
| [latex]{r}_{\perp }[/latex] | perpendicular lever arm |
| [latex]r[/latex] | radius of a nucleus |
| [latex]r[/latex] | radius of curvature |
| [latex]r[/latex] | resistivity |
| [latex]\text{r or rad}[/latex] | radiation dose unit |
| [latex]\text{rem}[/latex] | roentgen equivalent man |
| [latex]\text{rad}[/latex] | radian |
| [latex]\text{RBE}[/latex] | relative biological effectiveness |
| [latex]\text{RC}[/latex] | resistor and capacitor circuit |
| [latex]\text{rms}[/latex] | root mean square |
| [latex]{r}_{n}[/latex] | radius of the nth H-atom orbit |
| [latex]{R}_{\text{p}}[/latex] | total resistance of a parallel connection |
| [latex]{R}_{\text{s}}[/latex] | total resistance of a series connection |
| [latex]{R}_{\text{s}}[/latex] | Schwarzschild radius |
| [latex]S[/latex] | entropy |
| [latex]\mathbf{\text{S}}[/latex] | intrinsic spin (intrinsic angular momentum) |
| [latex]S[/latex] | magnitude of the intrinsic (internal) spin angular momentum |
| [latex]S[/latex] | shear modulus |
| [latex]S[/latex] | strangeness quantum number |
| [latex]s[/latex] | quark flavor strange |
| [latex]\text{s}[/latex] | second (fundamental SI unit of time) |
| [latex]s[/latex] | spin quantum number |
| [latex]\mathbf{\text{s}}[/latex] | total displacement |
| [latex]\text{sec}\phantom{\rule{0.20em}{0ex}}\theta[/latex] | secant |
| [latex]\text{sin}\phantom{\rule{0.20em}{0ex}}\theta[/latex] | sine |
| [latex]{s}_{z}[/latex] | z-component of spin angular momentum |
| [latex]T[/latex] | period—time to complete one oscillation |
| [latex]T[/latex] | temperature |
| [latex]{T}_{\text{c}}[/latex] | critical temperature—temperature below which a material becomes a superconductor |
| [latex]T[/latex] | tension |
| [latex]\text{T}[/latex] | tesla (magnetic field strength B) |
| [latex]t[/latex] | quark flavor top or truth |
| [latex]t[/latex] | time |
| [latex]{t}_{1/2}[/latex] | half-life—the time in which half of the original nuclei decay |
| [latex]\text{tan}\phantom{\rule{0.20em}{0ex}}\theta[/latex] | tangent |
| [latex]U[/latex] | internal energy |
| [latex]u[/latex] | quark flavor up |
| [latex]\text{u}[/latex] | unified atomic mass unit |
| [latex]\mathbf{\text{u}}[/latex] | velocity of an object relative to an observer |
| [latex]{\mathbf{\text{u}}}^{\mathbf{\text{'}}}[/latex] | velocity relative to another observer |
| [latex]V[/latex] | electric potential |
| [latex]V[/latex] | terminal voltage |
| [latex]\text{V}[/latex] | volt (unit) |
| [latex]V[/latex] | volume |
| [latex]\mathbf{\text{v}}[/latex] | relative velocity between two observers |
| [latex]v[/latex] | speed of light in a material |
| [latex]\mathbf{\text{v}}[/latex] | velocity |
| [latex]\overline{\mathbf{\text{v}}}[/latex] | average fluid velocity |
| [latex]{V}_{\text{B}}-{V}_{\text{A}}[/latex] | change in potential |
| [latex]{\mathbf{\text{v}}}_{\text{d}}[/latex] | drift velocity |
| [latex]{V}_{\text{p}}[/latex] | transformer input voltage |
| [latex]{V}_{\text{rms}}[/latex] | rms voltage |
| [latex]{V}_{\text{s}}[/latex] | transformer output voltage |
| [latex]{\mathbf{\text{v}}}_{\text{tot}}[/latex] | total velocity |
| [latex]{v}_{\text{w}}[/latex] | propagation speed of sound or other wave |
| [latex]{\mathbf{\text{v}}}_{\text{w}}[/latex] | wave velocity |
| [latex]W[/latex] | work |
| [latex]W[/latex] | net work done by a system |
| [latex]\text{W}[/latex] | watt |
| [latex]w[/latex] | weight |
| [latex]{w}_{\text{fl}}[/latex] | weight of the fluid displaced by an object |
| [latex]{W}_{\text{c}}[/latex] | total work done by all conservative forces |
| [latex]{W}_{\text{nc}}[/latex] | total work done by all nonconservative forces |
| [latex]{W}_{\text{out}}[/latex] | useful work output |
| [latex]X[/latex] | amplitude |
| [latex]\text{X}[/latex] | symbol for an element |
| [latex]{\text{}}^{Z}{X}_{N}[/latex] | notation for a particular nuclide |
| [latex]x[/latex] | deformation or displacement from equilibrium |
| [latex]x[/latex] | displacement of a spring from its undeformed position |
| [latex]x[/latex] | horizontal axis |
| [latex]{X}_{\text{C}}[/latex] | capacitive reactance |
| [latex]{X}_{\text{L}}[/latex] | inductive reactance |
| [latex]{x}_{\text{rms}}[/latex] | root mean square diffusion distance |
| [latex]y[/latex] | vertical axis |
| [latex]Y[/latex] | elastic modulus or Young’s modulus |
| [latex]Z[/latex] | atomic number (number of protons in a nucleus) |
| [latex]Z[/latex] | impedance |
