Lower case letters
Upper case Letters
NB it always precedes a unit symbol
A = area
A = nucleon number (atomic mass)
a = acceleration
a = Wein constant
a = alpha particle
B = magnetic flux density
b = beta particle
B = bell (sound intensity)
Bq = becquerel (activity)
C = capacitance
c = speed of light
c = specific heat capacity
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 = 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
F = force
f = frequency
f = focal length
fe = focal length of eyepiece lens
fo = focal length of objective lens
Φ = flux
φ = work function
g = gravitational field strength
g = acceleration due to gravity
G = gravitational constant
G = conductance
γ = gamma ray
h = height
h = Planck constant
H = dose equivalent>
H = hubble constant
Η = coefficient of viscosity
H = henry (inductance)
Hz = hertz (frequency)
I = current
I0 = peak current
I = sound intensity
I = moment of inertia
J = current density
J = moment of inertia
Θ = angle
k = Boltzmann constant
k = spring constant
K = kelvin (absolute temperature)
kg = kilogram (mass)
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
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 = 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
P = power
p = pressure
p = momentum
π = 3.14
p = pico
P = peta
x 10-12
x 1015
Q = charge
Q = heat energy
Q = quality factor
r = radius
R = resistance
R = molar gas constant
R = reacrion force
ρ = density
ρ = resistivity
rad = radian
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 = time
T = temperature
T = period of a waveform
T1/2 = half life
TE = effective half life
TB = bilogical half life
TP = physical half life
u = initial velocity
u = image distance
U = U-value
U = internal heat of a system
v = velocity
v = final velocity (when used in conjunction with 'u')
v = image distance
V = volume
V = potential difference
V0 = peak voltage
W = work done
ω = angular velocity
w = width of a fringe
Ω = ohm (electrical resistance)
W = watt(power)
Wb =weber (magnetic flux)
x = width
X = reactance
y = height
y = yocto
Y = yotta
x 10-24
x 1024
z = depth
Z = proton number (atomic number)
z = zepto
Z = zeta
x 10-21
x 1021
NB A level candidates are required to:
(a) define symbols used in an equation and
(b) the conditions under which the equations apply !!!