The Physics Alphabet

 
Lower case letters
Upper case Letters
Greek Letters * and their names
Equation Abbreviation for a Physical Quantity
Unit symbol
S.I. Prefix and its value
NB it always precedes a unit symbol
a
A
α
Α
alpha

A = area

A = nucleon number (atomic mass)

a = acceleration

a = Wein constant

a = alpha particle

  a = atto  x 10-18
b
B
β
Β
beta

B = magnetic flux density

b = beta particle

B = bell (sound intensity)

Bq = becquerel (activity)

   
c
C
χ
Χ
χ

C = capacitance

c = speed of light 

c = specific heat capacity

oC = degree Celsius (temperature) c = centi x 10-2
d
D
δ
Δ
δ

d = diameter

d = distance

D = distance from screen to fringe pattern

D = absorbed dose

Δ = change in

δ = little change in

D = dioptre (power of a lens)

dB = decibel (sound intensity)

d = deci

da = deca (or deka)

x 10-1

x 101

e
E
ε
Ε
ε

e = charge on an electron

E = energy

Ek = kinetic energy

E = electric field strength

E = Young's Modulus

ε = emf

ε = tensile strain

εo = permittivity of free space

eV = electron volt (energy) E = exa x 1018
f
F
φ
Φ
phi

F = force

f = frequency

f = focal length

fe = focal length of eyepiece lens

fo = focal length of objective lens

Φ = flux

φ = work function

F = farad (capacitance) f = femto x 10-15
g
G
γ
Γ
gamma

g = gravitational field strength

g = acceleration due to gravity

G = gravitational constant

G = conductance

γ = gamma ray

Gy = gray (absorbed dose) G = giga x 109
h
H
η
Η
eta

h = height

h = Planck constant

H = dose equivalent>

H = hubble constant

Η = coefficient of viscosity

H = henry (inductance)

Hz = hertz (frequency)

h = hecto x 102
I
I
ι
Ι
iota

I = current

I0 = peak current

I = sound intensity

I = moment of inertia

j
J
θ
Θ
theta

J = current density

J = moment of inertia

Θ = angle

J = joule (energy)    
k
K
κ
Κ
kappa

k = Boltzmann constant

k = spring constant

K = kelvin (absolute temperature)

kg = kilogram (mass)

k = kilo x 103
l
L
λ
Λ
lambda

l = length

l = specific latent heat

λ = wavelength

λ = decay constant

L = self inductance

L = angular momentum

ln = natural log of

log = log base 10 of

l = litre ( = 1000cm3) - volume measurement    
m
M
m
μ
mu

m = mass

M = magnification

μ = permeability

μ = coefficient of friction

m = metre (length)

m2= metre squared (area)

m3= metre cubed (volume)

M = mega

m = milli

μ = micro

x 106

x 10-3

x 10-6

n
N
ν
Ν
nu

N = number

NO = original number

NA = Avogadro constant

N = number of turns of wire

n = number of moles

n= order of diffraction

n = number of charge carriers per unit volume

n = refractive index

N = newton (force or weight) n = nano x 10-9
o
O
ο
Ο
omicron
NOT used for anything - it would too easily be confused with the number zero
p
P
π
Π
pi

P = power

p = pressure

p = momentum

π = 3.14

Pa = pascal (pressure)

p = pico

P = peta

x 10-12

x 1015

q
Q
     

Q = charge

Q = heat energy

Q = quality factor

     
r
R
ρ
Ρ
rho

r = radius

R = resistance

R = molar gas constant

R = reacrion force

ρ = density

ρ = resistivity

rad = radian

     
s
S
σ
Σ
sigma

s = displacement (vector version of distance)

s = slit width

σ = conductivity

σ = tensile stress

σ = Stefan constant

Σ = sum of

s = second (time)

Sv = sievert (dose equivalent)

S = siemens (conductance)

   
t
T
τ
Τ
tau

t = time

T = temperature

T = period of a waveform

T1/2 = half life

TE = effective half life

TB = bilogical half life

TP = physical half life

T = tesla (magnetic flux density) T = tera x 1012
u
U
υ
Υ
upsilon

u = initial velocity

u = image distance

U = U-value

U = internal heat of a system

u = atomic mass unit (mass at atomic levels)    
v
V
     

v = velocity

v = final velocity (when used in conjunction with 'u')

v = image distance

V = volume

V = potential difference

V0 = peak voltage

V = volt (electric potential)    
w
W
ω
Ω
omega

W = work done

ω = angular velocity

w = width of a fringe

Ω = ohm (electrical resistance)

W = watt(power)

Wb =weber (magnetic flux)

   
x
X
χ
Χ
chi

x = width

X = reactance

     
y
Y
ξ
Ξ
xi

y = height

 

y = yocto

Y = yotta

x 10-24

x 1024

z
Z
ζ
Ζ
zeta

z = depth

Z = proton number (atomic number)

 

z = zepto

Z = zeta

x 10-21

x 1021

The Greek letters are not in the order of the Greek alphabet but put next to their equivalent letter so that you can find them easily using the 'symbol' font in 'MSWord'
NOTE HOW IMPORTANT THE CASE OF THE LETTER IS - LEARN ACCEPTED SYMBOLS CAREFULLY!!!

NB A level candidates are required to:

 
(a) define symbols used in an equation and 
(b) the conditions under which the equations apply !!!


  LOJ Nov 1999

revised 2021