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In this glossary, key symbols and notation are briefly defined.
Symbol | Definition |
---|---|
$$\overline{\text{any symbol}}$$ | average (indicated by a bar over a symbol—e.g., $\overline{v}$ is average velocity) |
$$\xb0\text{C}$$ | Celsius degree |
$$\xb0\text{F}$$ | Fahrenheit degree |
$$\text{//}$$ | parallel |
$$\perp $$ | perpendicular |
$$\propto $$ | proportional to |
$$\pm $$ | plus or minus |
$${\phantom{\rule{0.25em}{0ex}}}_{0}$$ | zero as a subscript denotes an initial value |
$$\alpha $$ | alpha rays |
$$\alpha $$ | angular acceleration |
$$\alpha $$ | temperature coefficient(s) of resistivity |
$$\beta $$ | beta rays |
$$\beta $$ | sound level |
$$\beta $$ | volume coefficient of expansion |
$${\beta}^{-}$$ | electron emitted in nuclear beta decay |
$${\beta}^{+}$$ | positron decay |
$$\gamma $$ | gamma rays |
$$\gamma $$ | surface tension |
$$\gamma =1/\sqrt{1-{v}^{2}/{c}^{2}}$$ | a constant used in relativity |
$$\Delta $$ | change in whatever quantity follows |
$$\delta $$ | uncertainty in whatever quantity follows |
$$\mathrm{\Delta E}$$ | change in energy between the initial and final orbits of an electron in an atom |
$$\mathrm{\Delta E}$$ | uncertainty in energy |
$$\mathrm{\Delta m}$$ | difference in mass between initial and final products |
$$\mathrm{\Delta N}$$ | number of decays that occur |
$$\mathrm{\Delta p}$$ | change in momentum |
$$\mathrm{\Delta p}$$ | uncertainty in momentum |
$$\Delta {\text{PE}}_{\text{g}}$$ | change in gravitational potential energy |
$$\mathrm{\Delta \theta}$$ | rotation angle |
$$\mathrm{\Delta s}$$ | distance traveled along a circular path |
$$\mathrm{\Delta t}$$ | uncertainty in time |
$${\mathrm{\Delta t}}_{0}$$ | proper time as measured by an observer at rest relative to the process |
$$\mathrm{\Delta V}$$ | potential difference |
$$\mathrm{\Delta x}$$ | uncertainty in position |
$${\epsilon}_{0}$$ | permittivity of free space |
$$\eta $$ | viscosity |
$$\theta $$ | angle between the force vector and the displacement vector |
$$\theta $$ | angle between two lines |
$$\theta $$ | contact angle |
$$\theta $$ | direction of the resultant |
$${\theta}_{b}$$ | Brewster's angle |
$${\theta}_{c}$$ | critical angle |
$$\kappa $$ | dielectric constant |
$$\lambda $$ | decay constant of a nuclide |
$$\lambda $$ | wavelength |
$${\lambda}_{n}$$ | wavelength in a medium |
$${\mu}_{0}$$ | permeability of free space |
$${\mu}_{\text{k}}$$ | coefficient of kinetic friction |
$${\mu}_{\text{s}}$$ | coefficient of static friction |
$${v}_{e}$$ | electron neutrino |
$${\pi}^{+}$$ | positive pion |
$${\pi}^{-}$$ | negative pion |
$${\pi}^{0}$$ | neutral pion |
$$\rho $$ | density |
$${\rho}_{\text{c}}$$ | critical density, the density needed to just halt universal expansion |
$${\rho}_{\text{fl}}$$ | fluid density |
$${\overline{\rho}}_{\text{obj}}$$ | average density of an object |
$$\rho /{\rho}_{\text{w}}$$ | specific gravity |
$$\tau $$ | characteristic time constant for a resistance and inductance $(\text{RL})$ or resistance and capacitance $(\text{RC})$ circuit |
$$\tau $$ | characteristic time for a resistor and capacitor $(\text{RC})$ circuit |
$$\tau $$ | torque |
$${\rm Y}$$ | upsilon meson |
$$\Phi $$ | magnetic flux |
$$\varphi $$ | phase angle |
$$\Omega $$ | ohm (unit) |
$$\omega $$ | angular velocity |
$$A$$ | ampere (current unit) |
$$A$$ | area |
$$A$$ | cross-sectional area |
$$A$$ | total number of nucleons |
$$a$$ | acceleration |
$${a}_{\text{B}}$$ | Bohr radius |
$${a}_{\text{c}}$$ | centripetal acceleration |
$${a}_{\text{t}}$$ | tangential acceleration |
$$\text{AC}$$ | alternating current |
$$\text{AM}$$ | amplitude modulation |
$$\text{atm}$$ | atmosphere |
$$B$$ | baryon number |
$$B$$ | blue quark color |
$$\overline{B}$$ | antiblue (yellow) antiquark color |
$$b$$ | quark flavor bottom or beauty |
$$B$$ | bulk modulus |
$$B$$ | magnetic field strength |
$${\text{B}}_{\text{int}}$$ | electron’s intrinsic magnetic field |
$${\text{B}}_{\text{orb}}$$ | orbital magnetic field |
$$\text{BE}$$ | binding energy of a nucleus—it is the energy required to completely disassemble it into separate protons and neutrons |
$$\text{BE}/A$$ | binding energy per nucleon |
$$\text{Bq}$$ | becquerel—one decay per second |
$$C$$ | capacitance (amount of charge stored per volt) |
$$C$$ | coulomb (a fundamental SI unit of charge) |
$${C}_{\text{p}}$$ | total capacitance in parallel |
$${C}_{\text{s}}$$ | total capacitance in series |
$$\text{CG}$$ | center of gravity |
$$\text{CM}$$ | center of mass |
$$c$$ | quark flavor charm |
$$c$$ | specific heat |
$$c$$ | speed of light |
$$\text{Cal}$$ | kilocalorie |
$$\text{cal}$$ | calorie |
$${\text{COP}}_{\text{hp}}$$ | heat pump’s coefficient of performance |
$${\text{COP}}_{\text{ref}}$$ | coefficient of performance for refrigerators and air conditioners |
$$\text{cos}\phantom{\rule{0.20em}{0ex}}\theta $$ | cosine |
$$\text{cot}\phantom{\rule{0.20em}{0ex}}\theta $$ | cotangent |
$$\text{csc}\phantom{\rule{0.20em}{0ex}}\theta $$ | cosecant |
$$D$$ | diffusion constant |
$$d$$ | displacement |
$$d$$ | quark flavor down |
$$\text{dB}$$ | decibel |
$${d}_{\text{i}}$$ | distance of an image from the center of a lens |
$${d}_{\text{o}}$$ | distance of an object from the center of a lens |
$$\text{DC}$$ | direct current |
$$E$$ | electric field strength |
$$\epsilon $$ | emf (voltage) or Hall electromotive force |
$$\text{emf}$$ | electromotive force |
$$E$$ | energy of a single photon |
$$E$$ | nuclear reaction energy |
$$E$$ | relativistic total energy |
$$E$$ | total energy |
$${E}_{0}$$ | ground state energy for hydrogen |
$${E}_{0}$$ | rest energy |
$$\text{EC}$$ | electron capture |
$${E}_{\text{cap}}$$ | energy stored in a capacitor |
$$\text{Eff}$$ | efficiency—the useful work output divided by the energy input |
$${\text{Eff}}_{\text{C}}$$ | Carnot efficiency |
$${E}_{\text{in}}$$ | energy consumed (food digested in humans) |
$${E}_{\text{ind}}$$ | energy stored in an inductor |
$${E}_{\text{out}}$$ | energy output |
$$e$$ | emissivity of an object |
$${e}^{+}$$ | antielectron or positron |
$$\text{eV}$$ | electron volt |
$$\text{F}$$ | farad (unit of capacitance, a coulomb per volt) |
$$\text{F}$$ | focal point of a lens |
$$\mathbf{\text{F}}$$ | force |
$$F$$ | magnitude of a force |
$$F$$ | restoring force |
$${F}_{\text{B}}$$ | buoyant force |
$${F}_{\text{c}}$$ | centripetal force |
$${F}_{\text{i}}$$ | force input |
$${\mathbf{\text{F}}}_{\text{net}}$$ | net force |
$${F}_{\text{o}}$$ | force output |
$$\text{FM}$$ | frequency modulation |
$$f$$ | focal length |
$$f$$ | frequency |
$${f}_{0}$$ | resonant frequency of a resistance, inductance, and capacitance $(\text{RLC})$ series circuit |
$${f}_{0}$$ | threshold frequency for a particular material (photoelectric effect) |
$${f}_{1}$$ | fundamental |
$${f}_{2}$$ | first overtone |
$${f}_{3}$$ | second overtone |
$${f}_{\text{B}}$$ | beat frequency |
$${f}_{\text{k}}$$ | magnitude of kinetic friction |
$${f}_{\text{s}}$$ | magnitude of static friction |
$$G$$ | gravitational constant |
$$G$$ | green quark color |
$$\overline{G}$$ | antigreen (magenta) antiquark color |
$$g$$ | acceleration due to gravity |
$$g$$ | gluons (carrier particles for strong nuclear force) |
$$h$$ | change in vertical position |
$$h$$ | height above some reference point |
$$h$$ | maximum height of a projectile |
$$h$$ | Planck's constant |
$$\text{hf}$$ | photon energy |
$${h}_{\text{i}}$$ | height of the image |
$${h}_{\text{o}}$$ | height of the object |
$$I$$ | electric current |
$$I$$ | intensity |
$$I$$ | intensity of a transmitted wave |
$$I$$ | moment of inertia (also called rotational inertia) |
$${I}_{0}$$ | intensity of a polarized wave before passing through a filter |
$${I}_{\text{ave}}$$ | average intensity for a continuous sinusoidal electromagnetic wave |
$${I}_{\text{rms}}$$ | average current |
$$\text{J}$$ | joule |
$$J/\text{\Psi}$$ | Joules/psi meson |
$$\text{K}$$ | kelvin |
$$k$$ | Boltzmann constant |
$$k$$ | force constant of a spring |
$${K}_{\alpha}$$ | x rays created when an electron falls into an $n=1$ shell vacancy from the $n=3$ shell |
$${K}_{\beta}$$ | x rays created when an electron falls into an $n=2$ shell vacancy from the $n=3$ shell |
$$\text{kcal}$$ | kilocalorie |
$$\text{KE}$$ | translational kinetic energy |
$$\text{KE}+\text{PE}$$ | mechanical energy |
$${\text{KE}}_{e}$$ | kinetic energy of an ejected electron |
$${\text{KE}}_{\text{rel}}$$ | relativistic kinetic energy |
$${\text{KE}}_{\text{rot}}$$ | rotational kinetic energy |
$$\overline{\text{KE}}$$ | thermal energy |
$$\text{kg}$$ | kilogram (a fundamental SI unit of mass) |
$$L$$ | angular momentum |
$$\text{L}$$ | liter |
$$L$$ | magnitude of angular momentum |
$$L$$ | self-inductance |
$$\ell $$ | angular momentum quantum number |
$${L}_{\alpha}$$ | x rays created when an electron falls into an $n=2$ shell from the $n=3$ shell |
$${L}_{e}$$ | electron total family number |
$${L}_{\mu}$$ | muon family total number |
$${L}_{\tau}$$ | tau family total number |
$${L}_{\text{f}}$$ | heat of fusion |
$${L}_{\text{f}}\phantom{\rule{0.20em}{0ex}}\text{and}\phantom{\rule{0.20em}{0ex}}{L}_{\text{v}}$$ | latent heat coefficients |
$${\text{L}}_{\text{orb}}$$ | orbital angular momentum |
$${L}_{\text{s}}$$ | heat of sublimation |
$${L}_{\text{v}}$$ | heat of vaporization |
$${L}_{z}$$ | z - component of the angular momentum |
$$M$$ | angular magnification |
$$M$$ | mutual inductance |
$$\text{m}$$ | indicates metastable state |
$$m$$ | magnification |
$$m$$ | mass |
$$m$$ | mass of an object as measured by a person at rest relative to the object |
$$\text{m}$$ | meter (a fundamental SI unit of length) |
$$m$$ | order of interference |
$$m$$ | overall magnification (product of the individual magnifications) |
$$m\left({\text{}}^{A}\text{X}\right)$$ | atomic mass of a nuclide |
$$\text{MA}$$ | mechanical advantage |
$${m}_{\text{e}}$$ | magnification of the eyepiece |
$${m}_{e}$$ | mass of the electron |
$${m}_{\ell}$$ | angular momentum projection quantum number |
$${m}_{n}$$ | mass of a neutron |
$${m}_{\text{o}}$$ | magnification of the objective lens |
$$\text{mol}$$ | mole |
$${m}_{p}$$ | mass of a proton |
$${m}_{\text{s}}$$ | spin projection quantum number |
$$N$$ | magnitude of the normal force |
$$\text{N}$$ | newton |
$$\mathbf{\text{N}}$$ | normal force |
$$N$$ | number of neutrons |
$$n$$ | index of refraction |
$$n$$ | number of free charges per unit volume |
$${N}_{\text{A}}$$ | Avogadro's number |
$${N}_{\text{r}}$$ | Reynolds number |
$$\text{N}\cdot \text{m}$$ | newton-meter (work-energy unit) |
$$\text{N}\cdot \text{m}$$ | newtons times meters (SI unit of torque) |
$$\text{OE}$$ | other energy |
$$P$$ | power |
$$P$$ | power of a lens |
$$P$$ | pressure |
$$\mathbf{\text{p}}$$ | momentum |
$$p$$ | momentum magnitude |
$$p$$ | relativistic momentum |
$${\mathbf{\text{p}}}_{\text{tot}}$$ | total momentum |
$${\mathbf{\text{p}}}_{\text{tot}}^{\text{'}}$$ | total momentum some time later |
$${P}_{\text{abs}}$$ | absolute pressure |
$${P}_{\text{atm}}$$ | atmospheric pressure |
$${P}_{\text{atm}}$$ | standard atmospheric pressure |
$$\text{PE}$$ | potential energy |
$${\text{PE}}_{\text{el}}$$ | elastic potential energy |
$${\text{PE}}_{\text{elec}}$$ | electric potential energy |
$${\text{PE}}_{\text{s}}$$ | potential energy of a spring |
$${P}_{\text{g}}$$ | gauge pressure |
$${P}_{\text{in}}$$ | power consumption or input |
$${P}_{\text{out}}$$ | useful power output going into useful work or a desired, form of energy |
$$Q$$ | latent heat |
$$Q$$ | net heat transferred into a system |
$$Q$$ | flow rate—volume per unit time flowing past a point |
$$+Q$$ | positive charge |
$$-Q$$ | negative charge |
$$q$$ | electron charge |
$${q}_{p}$$ | charge of a proton |
$$q$$ | test charge |
$$\text{QF}$$ | quality factor |
$$R$$ | activity, the rate of decay |
$$R$$ | radius of curvature of a spherical mirror |
$$R$$ | red quark color |
$$\overline{R}$$ | antired (cyan) quark color |
$$R$$ | resistance |
$$\text{R}$$ | resultant or total displacement |
$$R$$ | Rydberg constant |
$$R$$ | universal gas constant |
$$r$$ | distance from pivot point to the point where a force is applied |
$$r$$ | internal resistance |
$${r}_{\perp}$$ | perpendicular lever arm |
$$r$$ | radius of a nucleus |
$$r$$ | radius of curvature |
$$r$$ | resistivity |
$$\text{r or rad}$$ | radiation dose unit |
$$\text{rem}$$ | roentgen equivalent man |
$$\text{rad}$$ | radian |
$$\text{RBE}$$ | relative biological effectiveness |
$$\text{RC}$$ | resistor and capacitor circuit |
$$\text{rms}$$ | root mean square |
$${r}_{n}$$ | radius of the n th H-atom orbit |
$${R}_{\text{p}}$$ | total resistance of a parallel connection |
$${R}_{\text{s}}$$ | total resistance of a series connection |
$${R}_{\text{s}}$$ | Schwarzschild radius |
$$S$$ | entropy |
$$\mathbf{\text{S}}$$ | intrinsic spin (intrinsic angular momentum) |
$$S$$ | magnitude of the intrinsic (internal) spin angular momentum |
$$S$$ | shear modulus |
$$S$$ | strangeness quantum number |
$$s$$ | quark flavor strange |
$$\text{s}$$ | second (fundamental SI unit of time) |
$$s$$ | spin quantum number |
$$\mathbf{\text{s}}$$ | total displacement |
$$\text{sec}\phantom{\rule{0.20em}{0ex}}\theta $$ | secant |
$$\text{sin}\phantom{\rule{0.20em}{0ex}}\theta $$ | sine |
$${s}_{z}$$ | z -component of spin angular momentum |
$$T$$ | period—time to complete one oscillation |
$$T$$ | temperature |
$${T}_{\text{c}}$$ | critical temperature—temperature below which a material becomes a superconductor |
$$T$$ | tension |
$$\text{T}$$ | tesla (magnetic field strength B ) |
$$t$$ | quark flavor top or truth |
$$t$$ | time |
$${t}_{1/2}$$ | half-life—the time in which half of the original nuclei decay |
$$\text{tan}\phantom{\rule{0.20em}{0ex}}\theta $$ | tangent |
$$U$$ | internal energy |
$$u$$ | quark flavor up |
$$\text{u}$$ | unified atomic mass unit |
$$\mathbf{\text{u}}$$ | velocity of an object relative to an observer |
$${\mathbf{\text{u}}}^{\mathbf{\text{'}}}$$ | velocity relative to another observer |
$$V$$ | electric potential |
$$V$$ | terminal voltage |
$$\text{V}$$ | volt (unit) |
$$V$$ | volume |
$$\mathbf{\text{v}}$$ | relative velocity between two observers |
$$v$$ | speed of light in a material |
$$\mathbf{\text{v}}$$ | velocity |
$$\overline{\mathbf{\text{v}}}$$ | average fluid velocity |
$${V}_{\text{B}}-{V}_{\text{A}}$$ | change in potential |
$${\mathbf{\text{v}}}_{\text{d}}$$ | drift velocity |
$${V}_{\text{p}}$$ | transformer input voltage |
$${V}_{\text{rms}}$$ | rms voltage |
$${V}_{\text{s}}$$ | transformer output voltage |
$${\mathbf{\text{v}}}_{\text{tot}}$$ | total velocity |
$${v}_{\text{w}}$$ | propagation speed of sound or other wave |
$${\mathbf{\text{v}}}_{\text{w}}$$ | wave velocity |
$$W$$ | work |
$$W$$ | net work done by a system |
$$\text{W}$$ | watt |
$$w$$ | weight |
$${w}_{\text{fl}}$$ | weight of the fluid displaced by an object |
$${W}_{\text{c}}$$ | total work done by all conservative forces |
$${W}_{\text{nc}}$$ | total work done by all nonconservative forces |
$${W}_{\text{out}}$$ | useful work output |
$$X$$ | amplitude |
$$\text{X}$$ | symbol for an element |
$${\text{}}^{Z}{X}_{N}$$ | notation for a particular nuclide |
$$x$$ | deformation or displacement from equilibrium |
$$x$$ | displacement of a spring from its undeformed position |
$$x$$ | horizontal axis |
$${X}_{\text{C}}$$ | capacitive reactance |
$${X}_{\text{L}}$$ | inductive reactance |
$${x}_{\text{rms}}$$ | root mean square diffusion distance |
$$y$$ | vertical axis |
$$Y$$ | elastic modulus or Young's modulus |
$$Z$$ | atomic number (number of protons in a nucleus) |
$$Z$$ | impedance |
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