3. Predefined Quantities¶
Definitions of commonly used quantities and units.
3.1. Mass¶
Reference unit: Kilogram (‘kg’)
Predefined units:
Symbol |
Name |
Definition |
Equivalent in ‘kg’ |
|---|---|---|---|
mg |
Milligram |
0.001·g |
0.000001 |
ct |
Carat |
0.2·g |
0.0002 |
g |
Gram |
0.001·kg |
0.001 |
oz |
Ounce |
0.0625·lb |
0.028349523125 |
lb |
Pound |
0.45359237·kg |
0.45359237 |
st |
Stone |
14·lb |
6.35029318 |
t |
Tonne |
1000·kg |
1000 |
3.2. Length¶
Reference unit: Metre (‘m’)
Predefined units:
Symbol |
Name |
Definition |
Equivalent in ‘m’ |
|---|---|---|---|
nm |
Nanometre |
0.000000001·m |
0.000000001 |
µm |
Micrometre |
0.000001·m |
0.000001 |
mm |
Millimetre |
0.001·m |
0.001 |
cm |
Centimetre |
0.01·m |
0.01 |
in |
Inch |
2.54·cm |
0.0254 |
dm |
Decimetre |
0.1·m |
0.1 |
ft |
Foot |
12·in |
0.3048 |
yd |
Yard |
3·ft |
0.9144 |
ch |
Chain |
22·yd |
20.1168 |
fur |
Furlog |
10·ch |
201.168 |
km |
Kilometre |
1000·m |
1000 |
mi |
Mile |
8·fur |
1609.344 |
3.3. Duration¶
Reference unit: Second (‘s’)
Predefined units:
Symbol |
Name |
Definition |
Equivalent in ‘s’ |
|---|---|---|---|
ns |
Nanosecond |
0.000000001·s |
0.000000001 |
µs |
Microsecond |
0.000001·s |
0.000001 |
ms |
Millisecond |
0.001·s |
0.001 |
min |
Minute |
60·s |
60 |
h |
Hour |
60·min |
3600 |
d |
Day |
24·h |
86400 |
3.4. Area¶
Definition: Length²
Reference unit: Square Metre (‘m²’)
Predefined units:
Symbol |
Name |
Definition |
Equivalent in ‘m²’ |
|---|---|---|---|
mm² |
Square Millimetre |
mm² |
0.000001 |
cm² |
Square Centimetre |
cm² |
0.0001 |
in² |
Square Inch |
in² |
0.00064516 |
dm² |
Square Decimetre |
dm² |
0.01 |
ft² |
Square Foot |
ft² |
0.09290304 |
yd² |
Square Yard |
yd² |
0.83612736 |
a |
Are |
100·m² |
100 |
ac |
Acre |
4840·yd² |
4046.8564224 |
ha |
Hectare |
100·a |
10000 |
km² |
Square Kilometre |
km² |
1000000 |
mi² |
Square Mile |
mi² |
2589988.110336 |
3.5. Volume¶
Definition: Length³
Reference unit: Cubic Metre (‘m³’)
Predefined units:
Symbol |
Name |
Definition |
Equivalent in ‘m³’ |
|---|---|---|---|
mm³ |
Cubic Millimetre |
mm³ |
0.000000001 |
cm³ |
Cubic Centimetre |
cm³ |
0.000001 |
ml |
Millilitre |
0.001·l |
0.000001 |
cl |
Centilitre |
0.01·l |
0.00001 |
in³ |
Cubic Inch |
in³ |
0.000016387064 |
dl |
Decilitre |
0.1·l |
0.0001 |
dm³ |
Cubic Decimetre |
dm³ |
0.001 |
l |
Litre |
0.001·m³ |
0.001 |
ft³ |
Cubic Foot |
ft³ |
0.028316846592 |
yd³ |
Cubic Yard |
yd³ |
0.764554857984 |
km³ |
Cubic Kilometre |
km³ |
1000000000 |
3.6. Velocity¶
Definition: Length/Duration
Reference unit: Metre per Second (‘m/s’)
Predefined units:
Symbol |
Name |
Definition |
Equivalent in ‘m/s’ |
|---|---|---|---|
km/h |
Kilometre per hour |
km/h |
5/18 |
ft/s |
Foot per Second |
ft/s |
0.3048 |
mph |
Mile per Hour |
mi/h |
0.44704 |
3.7. Acceleration¶
Definition: Length/Duration²
Reference unit: Metre per Second squared (‘m/s²’)
Predefined units:
Symbol |
Name |
Definition |
Equivalent in ‘m/s²’ |
|---|---|---|---|
mps² |
Mile per Second squared |
mi/s² |
1609.344 |
3.8. Force¶
Definition: Mass·Acceleration
Reference unit: Newton (‘N’ = ‘kg·m/s²’)
Predefined units:
Symbol |
Name |
Definition |
Equivalent in ‘N’ |
|---|---|---|---|
J/m |
Joule per Metre |
J/m |
1 |
3.9. Energy¶
Definition: Force·Length
Reference unit: Joule (‘J’ = ‘N·m’ = ‘kg·m²/s²’)
Predefined units:
Symbol |
Name |
Definition |
Equivalent in ‘J’ |
|---|---|---|---|
Nm |
Newton Meter |
N·m |
1 |
Ws |
Watt Second |
W·s |
1 |
kWh |
Kilowatt Hour |
kW·h |
3600000 |
3.10. Power¶
Definition: Energy/Duration
Reference unit: Watt (‘W’ = ‘J/s’ = ‘kg·m²/s³’)
Predefined units:
Symbol |
Name |
Definition |
Equivalent in ‘W’ |
|---|---|---|---|
mW |
Milliwatt |
0.001·W |
0.001 |
kW |
Kilowatt |
1000·W |
1000 |
MW |
Megawatt |
1000000·W |
1000000 |
GW |
Gigawatt |
1000000000·W |
1000000000 |
TW |
Terawatt |
1000000000000·W |
1000000000000 |
3.11. Frequency¶
Definition: 1/Duration
Reference unit: Hertz (‘Hz’ = ‘1/s’)
Predefined units:
Symbol |
Name |
Definition |
Equivalent in ‘Hz’ |
|---|---|---|---|
kHz |
Kilohertz |
1000·Hz |
1000 |
MHz |
Megahertz |
1000000·Hz |
1000000 |
GHz |
Gigahertz |
1000000000·Hz |
1000000000 |
3.12. DataVolume¶
Reference unit: Byte (‘B’)
Predefined units:
Symbol |
Name |
Definition |
Equivalent in ‘B’ |
|---|---|---|---|
b |
Bit |
0.125·B |
0.125 |
kb |
Kilobit |
1000·b |
125 |
Kib |
Kibibit |
1024·b |
128 |
kB |
Kilobyte |
1000·B |
1000 |
KiB |
Kibibyte |
1024·B |
1024 |
Mb |
Megabit |
1000000·b |
125000 |
Mib |
Mebibit |
1048576·b |
131072 |
MB |
Megabyte |
1000000·B |
1000000 |
MiB |
Mebibyte |
1048576·B |
1048576 |
Gb |
Gigabit |
1000000000·b |
125000000 |
Gib |
Gibibit |
1073741824·b |
134217728 |
GB |
Gigabyte |
1000000000·B |
1000000000 |
GiB |
Gibibyte |
1073741824·B |
1073741824 |
Tb |
Terabit |
1000000000000·b |
125000000000 |
Tib |
Tebibit |
1099511627776·b |
137438953472 |
TB |
Terabyte |
1000000000000·B |
1000000000000 |
TiB |
Tebibyte |
1099511627776·B |
1099511627776 |
3.13. DataThroughput¶
Definition: DataVolume/Duration
Reference unit: Byte per Second (‘B/s’)
Predefined units:
Symbol |
Name |
Definition |
Equivalent in ‘B/s’ |
|---|---|---|---|
b/s |
Bit per Second |
b/s |
0.125 |
kb/s |
Kilobit per Second |
1000·b/s |
125 |
Kib/s |
Kibibit per Second |
1024·b/s |
128 |
kB/s |
Kilobyte per Second |
1000·B/s |
1000 |
KiB/s |
Kibibyte per Second |
1024·B/s |
1024 |
Mb/s |
Megabit per Second |
1000000·b/s |
125000 |
Mib/s |
Mebibit per Second |
1048576·b/s |
131072 |
MB/s |
Megabyte per Second |
1000000·B/s |
1000000 |
MiB/s |
Mebibyte per Second |
1048576·B/s |
1048576 |
Gb/s |
Gigabit per Second |
1000000000·b/s |
125000000 |
Gib/s |
Gibibit per Second |
1073741824·b/s |
134217728 |
GB/s |
Gigabyte per Second |
1000000000·B/s |
1000000000 |
GiB/s |
Gibibyte per Second |
1073741824·B/s |
1073741824 |
Tb/s |
Terabit per Second |
1000000000000·b/s |
125000000000 |
Tib/s |
Tebibit per Second |
1099511627776·b/s |
137438953472 |
TB/s |
Terabyte per Second |
1000000000000·B/s |
1000000000000 |
TiB/s |
Tebibyte per Second |
1099511627776·B/s |
1099511627776 |
3.14. Temperature¶
Predefined units:
Symbol |
Name |
Equivalents |
|---|---|---|
°C |
Degree Celsius |
0 °C = 32 °F = 273,25 K |
°F |
Degree Fahrenheit |
0 °F ≅ -17.778 °C ≅ 255.372 K |
K |
Kelvin |
0 K = -273,25 °C = -459.67 °F |
Temperature units are converted using the following formulas:
from to |
Celsius |
Fahrenheit |
Kelvin |
|---|---|---|---|
Celsius |
[°F] = [°C] * 9/5 + 32 |
[K] = [°C] + 273.15 |
|
Fahrenheit |
[°C] = ([°F] - 32) * 5/9 |
[K] = ([°F] + 459.67) * 5/9 |
|
Kelvin |
[°C] = [K] - 273.15 |
[°F] = [K] * 9/5 - 459.67 |