length
| The Metric
| GB and US
|
10 millimetres (mm)
100 centimetres
1000 metres
| = 1 centimetre (cm)
= 1 metre (m)
= 1 kilometre (km)
| = 0∙3937 inches (in)
= 39∙37 inches or 1∙094 yards (yd)
= 0∙62137 miles or about 5/8 mile
|
surface
|
|
|
100 square metres (m2)
100 acres
100 hectares
| = 1 are (a)
= 1 hectare (ha)
= 1 square kilometre (km2)
| = 0∙0247 acres
= 2∙471 acres
= 0∙386 square miles
|
weight
|
|
|
10 milligrams (mg)
100 centigrams
1000 grams
1000 kilograms
| = 1 centigram (cg)
= 1 gram (g)
= 1 kilogram (kg)
= 1 tonne
| = 0∙1543 grains
= 15∙4323 grains
= 2∙2046 pounds
= 19∙684 cwt
|
capacity
|
|
|
1000 millilitres (ml)
10 litres
| = 1 litre (1)
= 1 decalitre (dl)
| = 1∙75 pints (2∙101 US pints)
= 2∙1997 gallons (2∙63 US gallons)
|
Appendix 7. Quantities, Units and Symbols
__________________________________________________________________ QUANTITY SYMBOL SI UNIT SYMBOL DERIVATION
acceleration
acceleration due to gravity
amount of substance
amplification factor
angle
—, of incidence
—, of refraction
—, Bragg
—, critical
anode slope
resistance
| a
g
n
μ
θ1,φ1,α 1
i
r
θ
c
RA
| m s –2
m s –2
mole
a ratio
—
degree or
radian
degree or
radian
number
degree or
radian
ohm
| —
—
mol
—
—
°
°
—
°
Ω
| velocity/time velocity/time
mole fraction (n) used
—
—
—
—
—
—
∆Va/∆Va
|
area
atomic number
Avogadro constant
breadth
capacitance
charge, electric
—, on electron
conductance
current, electric
decay constant
density
distance along path
efficiency
electrochemical
equivalent
electromotive force
electron
energy
—, kinetic
—, potential
Faraday constant
field strength, elec-
tric
magnetic
flux, magnetic
flux density
| A
Z
L, NA
b
С
Q
e
G
I
λ
p
s
η
z
E
e
E
Ek
Ep
F
E
H
Ф
В
| metres square
a number
number
metre
farad
coulomb
coulomb
ohm–1
ampere
a ratio
kg m–3
metre
a ratio
g C -1
volt
joule
joule
joule
coulomb mol-1
V m-1
ampereturns
weber
tesla
| m2
—
—
m
F
С
С
Ω –1
A
—
—
m
—
—
V
J
J
J
С mol-1
—
—
Wb
Т
| l x b
number of protons
—
fundamental unit
charge/p.d.
current x time
1∙6 х 10-19 С
reciprocal of resistance
fundamental unit
—
m/V
fundamental unit
work output/work input
mass/charge
energy/charge
N m
N m. Ek = ½mv2
N m. Ep = mgh
96 500 C mol-1
potential gradient:
p.d./dist.
current x no. of turns
e.m.f./rate of change of flux
flux/area
|
focal length
forse
free energy
frequency
gas constant
half-life, radioacti-vity
heat capacity
heat of reaction
heat capacity, spe-
cific
heat, quantity of height
image distance
inductance, mutual
—, self
intensity of radia-tion
latent heat
—, specific
—, molar
length
magnetizing force
magnetic moment
magnification,
| f
F
∆G
f
r
t½
С
∆H
c
q
h
v
M
L
I
L
l
Lm
l
H
m
m
| metre
newton
joule
hertz
joule
second
J K - 1
joule
J K - 1 kg - 1
joule
metre
metre
henry
henry
a number
joule
J kg - 1
joule mol - 1
metre
ampereturns Wb m
a ratio
| M
N
J
Hz
J
s
—
J
—
J
m
m
H
H
—
J
—
J
m
—
—
—
| —
kg m s - 2
oscillations/time
energy
fundamental unit
quantity of heat/temp.
rise
heat energy
heat capacity/mass
energy
fundamental unit
fundamental unit
induced e.m.f./rate
of change of current
—
quantity of heat
quantity of heat
quantity of heat
fundamental unit
—
torque in unit
magnetic field
—
|
linear
mass
—, number
molar volume
molar solution
moment of force
neutron number
number
—, of molecules
—, of turns on coil
—, order of spectrum
object distance
peak current
peak e.m.f.
period
permeability
—,of vacuum
—, relative
permittivity
—,of vacuum
—, relative
potential, electric
potential difference
power
pressure
radius
|
m
A
Vm
M
—
N
n
N
n
p
и
I0
E0
Т
μ
μ0
μr
ε
ε0
εr
V
V
P
p
r
|
kilogramme
a number
(dm3)
a ratio
N m
a number
—
—
a number
a number
metre
ampere
volt
second
H m-1
H m-1
a ratio
F m-1
F m-1
a ratio
volt
volt
watt
pascal
metre
|
kg
—
—
—
—
—
—
—
—
—
m
A
V
s
—
—
—
—
—
—
V
V
W
Pa
m
|
fundamental unit
number of neutrons + protons
volume of 1 mole
moles/dm3
force x perp. distance
number of neutrons
—
—
—
—
fundamental unit
see current
see e.m.f.
fundamental unit
henry/metre
—
μ = μ/ μ0
farad/metre
farad/metre
εr = ε/ ε0
energy/charge
energy/charge
J s-1
N m-2 : force/area
fundamental unit
|
reactance
refractive index
resistance
resistivity, electrical
relative density
r.m.s. current
r.m.s. voltage
slit separation
tension
temperature, Celsius
temp, interval
temp, absolute
thickness
time
torque
turns ratio
(unit of electricity)
velocity
—, angular
—, of e.m. waves
—, of sound
volume
wavelength
work
weight
| X
n
R
ρ
d
I rms
V rms
S
T
θ
θ
T
d
t
Т
Т
—
u, v
ω
с
v
V
λ
w
W
| ohm
a ratio
ohm
ohm-metre
a ratio
ampere
volt
metre
newton
degree С
degree
kelvin
metre
second
N m
a ratio
k W h
m s –1
second –1
m s –1
m s –1
metre cubed
metre
joule
newton
| Ω
—
Ω
—
—
A
V
m
N
°С
° or К
K
m
s
—
—
—
—
s -1
—
—
m3
m
J
N
| E0 / l0
—
p.d./current
resistance x length
ρ sub /ρ water
see current
see e.m.f.
fundamental unit
see force
from kelvin
—
fundamental unit
fundamental unit
fundamental unit
see moment
nsec/nprim
kilowatt x hour
distance/time
angle/time
—
—
l x b x h
fundamental unit
force x distance (N m)
kg m s~2 or mg
|
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