08 Notation

This list describes several symbols that are commonly used within the body of the book.

Speed of light in a vacuum inertial frame: 2.99792458 × ${10}^8$ m/s ≈ 3 x ${10}^8$ m/s

Ε Efficiency; typically 0 ≤ & ≤ 1; unitless

g acceleration due to gravity: 9.8 m/s2 or ~10 m/s2

h Planck’s constant: 6.626 × ${10}^{-34}$ J. S

KB Boltzmann’s constant: 1.38 x ${10}^{-23}$ J/K

ΝΑ Avogadro’s number: 6.022 × ${10}^{23}$ particles per mole

AQ Change in thermal energy, in Joules

Re Radius of Earth: 6,378 km

Ro Radius of Sun: 695,700 km

reo Earth-Sun distance (1 AU): 149.6 million km

σ Stefan-Boltzmann constant: 5.67 x ${10}^{-8}$ W/K/m2

AS Change in entropy, in J/K

AT Change in temperature, typically in °C or Kelvin (K)

AW Change in energy-work performed, in Joules

Scale Factor Prefixes

Factor Letter Prefix Factor Letter Prefix

${10}^{-2}$ ${10}^{-18}$ -21

Z zepto 1021

Z zetta

a atto

1018 E exa

${10}^{-15}$ femto 1015 P

${10}^{-12}$ peta P

pico 1012 T tera

${10}^{-9}$ n nano 109

G ${10}^{-6}$ giga

μ micro 106

M ${10}^{-3}$ mega

m milli

103 k kilo