Deepermind Metric Units

Updated October 28, 2023

My business is fixing computers.  Call 972 978-9703
Deepermind Home Page

Prefix

Symbol

10n

US English Term

Decimal

Adoption
quetta Q 1030 nonillon 1 000 000 000 000 000 000 000 000 000 000 2022
ronna R 1027 octillion 1 000 000 000 000 000 000 000 000 000 2022

yotta

Y

 1024

septillion

1 000 000 000 000 000 000 000 000

1991

zetta

Z

 1021

sextillion

1 000 000 000 000 000 000 000

1991

exa

E

 1018

quintillion

1 000 000 000 000 000 000

1975

peta

P

 1015

quadrillion

1 000 000 000 000 000

1975

tera

T

 1012

trillion

1 000 000 000 000

1960

giga

G

 109

billion

1 000 000 000

1960

mega

M

 106

million

1000 000

1960

kilo

k

 103

thousand

1 000

1795

*hecto

h

 102

hundred

100

1795

*deca

da

 101

ten

10

1795

(unity)

(none)

100

one

1

ancient

*deci

d

 10−1

tenth

0.1

1795

*centi

c

 10−2

hundredth

0.01

1795

milli

m

 10−3

thousandth

0.001

1795

micro

µ

 10−6

millionth

0.000 001

1960

nano

n

 10−9

billionth

0.000 000 001

1960

pico

p

 10−12

trillionth

0.000 000 000 001

1960

femto

f

 10−15

quadrillionth

0.000 000 000 000 001

1964

atto

a

 10−18

quintillionth

0.000 000 000 000 000 001

1964

zepto

z

 10−21

sextillionth

0.000 000 000 000 000 000 001

1991

yocto

y

 10−24 

septillionth

0.000 000 000 000 000 000 000 001

1991

ronto r 10−27 octillionth 0.000 000 000 000 000 000 000 000 001 2022
quecto q 10−30 nonillionth 0.000 000 000 000 000 000 000 000 000 001 2022

*Note: Not based 1000x intervals.

Also see this web page for more examples.

 

Metric Units Examples

Prefix

Symbol

10n

US English Term

Length

quetta Q 1030 nonillion Jupiter weights ~2 Qg (gram)
Formally 1 Gegobyte
ronna R 1027 octillion Earth weights ~6 Rg (gram)

yotta

Y

 1024

septillion

Yottabyte =
1,208,925,819,614,629,174,706,176 bytes
Visible universe: 43 Ym
Hubble sphere radius = 14.4 billion light years where galaxies move away from Earth at the speed of light: 136 Ym

zetta

Z

 1021

sextillion

Our Milky Way Galaxy:  1 Zm

exa

E

 1018

quintillion

Distance to nearest stars: 1 Em

peta

P

 1015

quadrillion

Light year 9.46 Pm
Age if the universe 500 Ps

tera

T

 1012

trillion

Across the orbits of the outer planets 10 Tm

giga

G

 109

billion

Distance to the sun 150 Gm

mega

M

 106

million

Earth to Moon 384 Mm;  Diameter of Earth 12.7 Mm; Circumference of the Earth 40 Mn; Distance across USA  3.93 Mm

kilo

k

 103

thousand

Mt. Everest above sea level 8.85 km; Marathon 42 km

*hecto

h

 102

hundred

Sprint track race 100 m

*deca

da

 101

ten

City block about 80 m; Football field 91.7 m; Oak tree 10 m

(unity)

(none)

100

one

Man 1.8 m

*deci

d

 10−1

tenth

Hand 1

*centi

c

 10−2

hundredth

Finger nail, dime about 1 cm or 100 mm

milli

m

 10−3

thousandth

Tip of a pencil 1 mm

micro

µ, mc

 10−6

millionth

White blood cell 100 µm. Also written as mc (medical). E.g. mcg (microgram)

nano

n

 10−9

billionth

DNA 2.5 nm

pico

p

 10−12

trillionth

Atoms  62 to 520 pm

femto

f

 10−15

quadrillionth

Proton 1 fm

atto

a

 10−18

quintillionth

Quark 100 am; Unknown < 10 am

zepto

z

 10−21

sextillionth

Unknown

yocto

y

 10−24 

septillionth

Unknown
ronto r 10−27 octillionth
quecto q 10−30 nonillionth Weight of an electron ~1qg (gram)

 

Computer Prefixes

Computers are built around binary numbers.  Binary numbers 1, 2, 4, and 8 are written as 1, 10, 100 and 1000.  In binary there are just two symbols used 0 and 1. Every time you add another digit to the left of a binary number, you double the number.

We commonly use decimal notation which means very time you add another digit to the left of a binary number you multiply it by ten.

When a computer is built, it is built around binary numbers.  The number 1024 when written in binary is 1000000000.  You can see that binary numbers are awkward to write. Since 1024 is about 1000, the people started to call 1024 a "K". It is pretty close.  This is how much a kilobyte really is.

The next symbol was "M" and this was 1024 times 1024 which as pretty close to a million.  It actually is 1,049,576.  This is how much a megabyte really is.

As things got bigger, a "G" symbol was added.  This was 1024 times 1024 times 1024 or about a billion. But not exactly.  It really was 1,073,741,824. This is actually how much a gigabyte is.

Once again things grew in size.  A "T" symbol was added and this was 1024 raised to 4th power. The actual value was 1,099,511,627,776.  This is actually how much a terabyte is. You get 99.5 million bytes free.  That is nice.

To fix all this, in 1998, the International Electrotechnical Commission came up with their own prefixes.  The trouble was nobody paid attention. In theory it was a good idea.  Making Ki mean 1024, and K mean 1000 made sense.  But everyone liked K meaning 1024 in the computer world and 1000 for weights and measures. Just for fun here is a table of their "Standard Computer Prefixes" which never became standard.

International Electrotechnical Commission Computer Prefixes

Prefix

Symbol

10n

Number of Bits

kibi- Ki 210 1 024
mebi- Nu 220 1 048 576
gibi- Gi 230 1 073 741 824
tebi Ti 240 1 099 511 627 776
pebi- Pi 250 1 125 899 906 842 624
exbi- Ei 260 1 152 921 504 606 846 976


Actual Real World Computer Prefixes

Prefix

Symbol

2n

Number of Bits

Spelled Out
Bit -- 0 1 1 bit
Byte B 3 8 8 bits
Kilo KB 10 1 024 1024 bits
Mega MB 20 1 048 576 1024 Kilobytes
Giga GB 30 1 073 741 824 1024 Megabytes
Tera TB 40 1 099 511 627 776 1024Gigabytes
Peta PB 50 1 125 899 906 842 624 1024 Terabytes
Exa EB 60 1 152 921 504 606 846 976 1024 Petabytes

 

Electromagnetic Spectrum

Item

Wavelength

 

Frequency

 

Gamma radiation

< 10 pm  

  > 10 EHz

 
X Rays

 10 pm - 10 nm

 

30 PHz - 30 EHz

 
Vacuum Ultraviolet 40 -190 nm   1.57 - 7.5 PHz extreme > 100 nm
Ultraviolet UVC

220 -290 nm

  1.07 PHz - 3.0 PHz far 190 - 220 nm germicidal totally absorb by atmosphere
Ultraviolet UVB 290 - 320 nm   952 THz - 1.07 PHz middle 200 - 300 nm destructive sunburn
Ultraviolet UVA 320 - 400 nm   315 - 750 THz near 300 -400 nm tanning
Violet

400 - 424 nm

  707 - 750 THz Ref: Physics Hypertextbook
Blue

424 - 491 nm

 

610 - 707 THz

Green

491 - 575 nm

 

521 - 610 THz

Yellow

575 - 585 nm

512 - 521 THz

Orange

585 - 647 nm

 

463 - 512 THz

Red

647 - 700 nm

 

428 - 463 THz

Near Infrared

750 nm –1.4 µm

  214 - 400 THz

Defined by the water absorption, and commonly used in fiber optics, night vision goggles, TV clickers. Most cellphone cameras can see into this spectrum.

Short Wave Infrared

1.4-3 µm

 

214 - 100 THz

Water absorption occurs  band 1.45 µm.  Fiber optics band 1.53 to 1.560 µm 

Mid Wave Infrared

3–8 µm

  100 - 37.4 THz

Atmospheric window used for heat seeking guided missile 3–5 µm

Long Wave Infrared

8–15 µm

  19.9 - 37.4 THz

Thermal Infrared Region. Objects give off this type of radiation as a function of temperature.  Forward-looking infrared (FLIR) cameras use this part of the spectrum.

Far Infrared

15–1,000 µm

  3.00 - 19.7 THz

Cool objects (5 K and 340 K) radiation. Used to observe interstellar gases such as M82.

Microwave
Submillimeter

100 µm - 1 mm

 

300 GHz - 3000 GHz

 
Extreme EHF 1 - 10 mm   30            - 300 GHz  
Super SHF microwave 10 -100 mm   3              - 30 GHz  
Ultra High Freq.  UHF 100  mm - 1 m   300 MHz - 3 GHz Microwave Oven 122 mm, 2.45 GHz

Very High Freq.  VHF

1 - 10 m   30            - 300 MHz Microwave low end 1 m, 300 MHz

High Freq.  HF

10 - 100 m   3              - 30 MHz  
Medium MF 100 km - 1 Mm   300 kHz  - 3 MHz  
Low Freq. LF 1 - 10 km   30            - 300 kHz  
Very Low Freq. VLF 10 -100 km   3               - 30 kHz  
Extreme Low Freq. ELF 100 - 3 Mm   100 Hz     - 3 KHz  
Ultra Low Freq. ULF > 3 Mm   <100 Hz  
2 Meter Ham Band 2 m   149 MHz  
TV Channel 2 USA 5.55 m   54 MHz  

TV Channel 6 USA

3.65 m   82 MHz  

TV Channel 7 USA

1.72 m   174 MHz  

TV Channel 13 USA

1.42 m   210 MHz  

TV Channel 14 USA

0.63 m   470 MHz  

TV Channel 83 USA

0.34 m   884 MHz  
FM Radio USA 2.77 - 3.41 m   88 - 108 MHz  
Short Wave HF 9.99  - 176 m   1.7 - 30 MHz  
AM Broadcast Band (USA) 176 - 555 m   540 - 1.7 MHz  
WWVB 5.00 km   60 KHz  
AC Current 5.00 Mm   60 Hz Wave length is 3,090 Miles

 

Capacitor Conversion Values

Power of Ten

Microfarads

Nanofarads

Picofards

-6 1 uf 1 000 nf 1 000 000 pf
-7 .1 uf 100 nf 100 000pf
-8 .01 uf 10 nf 10 000pf
-9 .001 uf 1 nf 1000 pf
-10 .0 001 uf .1 nf 100 pf
-11 .00 001 uf .01 nf 10 pf
-12 .000 0001 uf .001 nf 1 pf

Thus 21010^(-9) f = 1 nf = .001 uf = 1000 pf.

WAVELENGHT and FREQUENCY CONVERSION

c = f * w

w = c/f

f= c/w

where: w = wavelength in meters, f = frequency in Hz

             c =velocity of light in a vacuum = 299,792,458 m/s

_____________________

For f in MHz

 f = 300/w  approximation

w = 300/f  approximation

_____________________

Dipole length Antenna Formulas (f is in MHz)

Antenna length in meters = 150/f

Antenna length in inches = 5905/f

Antenna length in feet = 492/f

In actual practice, the end effect should be considered.  The result from the above formula should be multiplied by about 0.95.

Antenna length in meters = 142.5/f

Antenna length in inches = 5609.75/f

Antenna length in feet = 467.4/f

If a quarter length antenna is being considered with an end effect included:

Antenna length in meters = 71.25/f

Antenna length in inches = 2,804.875/f

Antenna length in feet = 233.7/f

 

Radio Bands (VLF, LF, MF, HF, VHF, UHF, SHF, EHF) Allocations


George Norwood
KE5KDO
Contact george@deepermind.com
972 978-9703 


Back to Deepermind Main Page