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

a

A

alpha 
A
= area
A = nucleon
number (atomic mass)
a = acceleration
a =
Wein constant a
= alpha particle


a
= atto 
x
10^{18} 
b

B

b

B

beta 
B
= magnetic flux density
b
= beta particle

B
= bell (sound intensity)
Bq = becquerel (activity)



c

C

c

C

chi 
C
= capacitance
c = speed of light c = specific heat capacity

^{o}C
= degree Celsius^{ }(temperature) 
c
= centi 
x
10^{2} 
d

D

d

D

delta 
d
= diameter
d = distance
D = distance from screen
to fringe pattern
D = absorbed dose
D
= change in
d
= little change in

D
= dioptre (power of a lens)
dB = decibel (sound intensity)

d
= deci
da = deca (or deka)

x
10^{1}
x 10^{1}

e

E

e

E

epsilon 
e
= charge on an electron
E = energy
E_{k}
= kinetic energy
E = electric
field strength
E = Young's
Modulus
e
= emf
e
= tensile strain e_{o}_{
= permittivity of free space}

eV
= electron volt (energy) 
E
= exa 
x
10^{18} 
f

F

f

F

phi 
F
= force
f = frequency
f = focal length
f_{e} = focal length
of eyepiece lens
f_{o} = focal length
of objective lens
F
= flux
f
= work function

F
= farad (capacitance) 
f
= femto 
x
10^{15} 
g

G

g

G

gamma 
g
= gravitational field strength
g = acceleration
due to gravity
G = gravitational
constant
G = conductance g
= gamma ray

Gy
= gray (absorbed dose) 
G
= giga 
x
10^{9} 
h

H

h

H

eta 
h
= height
h = Planck constant
H = dose equivalent
H = hubble constant h
= coefficient of viscosity

H
= henry (inductance)
Hz = hertz (frequency)

h
= hecto 
x
10^{2} 
I

I

I

I

iota 
I
= current
I_{0} = peak current
I = sound intensity I = moment of inertia

Care!
Always 'top' and 'tail' I so that it can be differentiated from
1 or l

j

J

j

J

theta 
J
= current density
J = moment of inertia J
= angle

J
= joule (energy) 


k

K

k

K

kappa 
k
= Boltzmann constant
k = spring constant

K
= kelvin (absolute temperature)
kg = kilogram (mass)

k
= kilo 
x
10^{3} 
l

L

l

L

lamda 
l
= length
l = specific latent heat
l
= wavelength
l
= decay constant
L = self inductance
L = angular momentum
ln = natural log of log = log base 10 of

l
= litre ( = 1000cm^{3})  volume measurement 


m

M

m

M

mu 
m
= mass
M = magnification
m
= permeability m
= coefficient of friction

m
= metre (length)
m^{2}
= metre squared (area) m^{3}
= metre cubed (volume)

M
= mega
m = milli m
= micro

x
10^{6}
x 10^{3} x 10^{6}

n

N

n

N

nu 
N
= number
N_{O} = original
number
N_{A} = 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

o

O

omicron 
NOT used
for anything. it would too easily be confused with the number
zero

p

P

p

P

pi 
P
= power
p = pressure
p = momentum p
= 3.14

Pa
= pascal (pressure) 
p
= pico
P = peta

x
10^{12}
x 10^{15}

q

Q




Q
= charge
Q = heat
energy Q = quality
factor




r

R

r

R

rho 
r
= radius
R = resistance
R = molar gas constant
R = reacrion force
r
= density
r
= resistivity
rad = radian




s

S

s

S

sigma 
s
= displacement (vector version of distance)
s = slit width
s
= conductivity
s
= tensile stress
s
= Stefan constant
S
= sum of

s
= second (time)
Sv = sievert (dose equivalent) S = siemens (conductance)



t

T

t

T

tau 
t
= time
T = temperature
T = period of a waveform
T_{1/2} = half life
T_{E} = effective
half life
T_{B} = bilogical
half life T_{P} = physical
half life

T
= tesla (magnetic flux density) 
T
= tera 
x
10^{12} 
u

U

u

U

upsilon 
u
= initial velocity
u = image
distance
U = Uvalue 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 V_{0} = peak voltage

V
= volt (electric potential) 


w

W

w

W

omega 
W
= work done
w
= angular velocity w = width
of a fringe

W
= ohm (electrical resistance)
W = watt
(power) Wb =weber
(magnetic flux)



x

X

x

X

zeta 
x
= width
X = reactance




y

Y

y

Y

xi 
y
= height 



z

Z

z

Z

zeta 
z
= depth
Z = proton number (atomic
number)




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 !!!
