|
Units,
Constants
Standard
Values &
Equivalents
|
|
|
|
Unit
|
Symbol
|
Standard
|
| |
Length.
|
m
|
The
metre = I 650 763.73 wavelengths of the Kr 86 orange radiation (2p10-
5d5).
|
| |
Mass.
|
kg
|
The
kilogramme is the mass of the International Prototype kilogramme (a
Pt-Ir cylinder) at the Institute of Weights and Measures Paris.
|
| |
Time.
|
s
|
The
mean solar second.
|
| |
Force.
|
N
|
1
Newton (N) will accelerate I kgm at I m s-2.
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| |
Work.
|
J
|
I
joule (J) = 1 Nm.
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| |
Power.
|
W
|
1
W = 1J.s-1
|
| |
|
|
|
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C.G.S.
units.
|
|
|
| |
Force
|
|
1
dyn = 10-5N
|
| |
Work
|
|
1
erg = 10-7 J.
|
| |
|
|
|
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Velocity
of Light
|
|
2.998x108ms-1= 186300 ml s-5 |
| |
Permeability
of Vacuum (m.k.s.).
|
μ0
|
4π
x 10-7Hm-1
|
| |
Permittivity
of Vacuum (m.k.s)
|
Є0
|
8.854
x 10-12Fm-1
|
| |
Gravitational
constant
|
C
|
6.668
x 10-11 Nm-1 Kg -2
|
| |
Standard
acceleration of gravity.
|
g
|
9.807
ms-2
|
| |
|
|
32.I
ft s-2
|
| |
Standard
atmosphere
|
atm
|
10.13250
Nm-2
|
| |
Solar
year
|
|
365
days 5 hours 48 min 45.5
Sec
|
| |
Mean
solar second
|
|
1/86400
mean solar day
|
| |
|
|
|
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International
Temperature Scale of 1948
|
|
| |
b.p.
Oxygen
|
|
-182.97
oC
|
| |
m.p.
Ice
|
|
0 0C
at 1 std. atmosphere
|
| |
b.p.
Water
|
|
100 0C
..
|
| |
b.p.
Sulphur
|
|
444.6 0C
..
|
| |
f.p.
Silver
|
|
960.8 0C
..
|
| |
f.p.
Gold
|
|
1063 0C
..
|
| |
m.p.
Ice on Kelvin scale
|
|
273.20K.
|
| |
Triple
Pt. of water
|
|
0.010 0C. |
| |
International
Table calorie
|
calIT
|
4.187 J
|
| |
I
50C calorie. =.
|
cal15
|
4.186 J
|
| |
British
thermal unit.
|
Btu
|
778.2 ft lbf
|
| |
|
|
1055 J.
|
| |
Therm
|
therm
|
105 Btu
|
| |
Horsepower
|
hp
|
550 ft Ibf s-1
|
| |
|
|
745.7 W
|
| |
Electron
volt
|
ev
|
1.602 x 10-19 J.
|
| |
e.m.f.
of Normal Weston Cadmium cell
|
|
I.0l9v
|
| |
Standard
transmitted radio frequency.
|
Droitwich
(carrier)
|
200
kc/s.
|
| |
Standard
transmitted audio frequency.
|
B.B.C.
3rd Programme
|
400
c/s.
|
| |
Standard
concert pitch
|
A
|
440
c/s.
|
| |
Scientific
pitch
|
C
|
256
C/S.
|
| |
Standard
volume of perfect gas
|
Vo
|
22.42
m3 atm kmole-1
|
| |
Avogadro's
constant
|
N
|
6.0249
x 1026 kmole-1.
|
| |
Loschmidt's
constant
|
L0
|
2.687
x 1025 m-3 atm.
|
| |
Gas
constant.
|
Ro
|
8317
J(kmole 0K-1.
|
| |
Boltzmann's
constant
|
k
|
1.380
x 10-23 J 0K-1.
|
| |
Faraday's
constant
|
F
|
9.652
x 107 C kmole-1
|
| |
Electron
charge
|
e
|
1.602
x 10 -19C
|
| |
Electron
rest mass
|
m
|
9.108
x 10-31kg
|
| |
Electron
charge/mass ratio
|
e/m
|
1.759
x 1011 C kg-1
|
| |
Proton
rest mass.
|
mp
|
1.
672 x 10- 27 kg.
|
| |
Neutron
rest mass
|
mn
|
1.
674 x 10-27 kg.
|
| |
Proton
mass/electron mass
|
m/mp
|
1836.
|
| |
P!anck's
constant.
|
h
|
6.625
x 1034 Js.
|
| |
Wien's
law.
|
λmazT
|
28.98
x 10-4m 0K
|
| |
Stefan-Boltzmann
constant
|
α
|
0.5669
x 10-7 J m-2
|
| |
Mass
of Sun
|
|
1.987
x 1030 kg
|
| |
Mass
of Earth
|
|
5.975
x 1024 kg
|
| |
Mean
distance earth to sun
|
|
1.495
x 108 km
|
| |
|
|
92.89
x l06 ml.
|
| |
Earth’s
equatorial radius
|
|
6378
km
|
| |
|
|
3963
mls (miles)
|
| |
Earth’s
polar radius
|
|
6357
km
|
| |
|
|
3950
mls (miles)
|