Km and km: Is the Difference Real?

[YoshiMoshi]

Mod note: Moved from Precalc section of Homework & Coursework
1. Homework Statement

Km = 1024 m
km = 1000 m

Is this true or not? Because K = 2^10 while k = 10^3?

Homework Equations

The Attempt at a Solution

 

[DrClaude]

The SI system of units only allows the use of the kilo = 10³ with the symbol k, so "Km" is not valid.

 

[BvU]

Hi,

You want to confuse everyone ? Then do such things in your communication !

According to some 1998 standard you would use Kim for Kibi meter = 1024 m... (*)
But using that standard outside the IT world is nefarious. And inside, I 'm not aware it has gained any popularity either.

(*) Then there is a JEDEC standard draft that, again, should remain in the IT world, far, far from physics.

By the way, why did you post in a math forum ?

 

[Tunalover]

The following link provides proper guidance on when to use a capital letter for a metric unit:
https://www.nist.gov/pml/weights-and-measures/writing-metric-units
Prefixes are capitalized at 10⁶ and larger. All smaller units are lower case.
nano=n
pico=p
milli=m
deci=d
kilo=k
Mega=M
Giga=G
Tera=T

 

[anorlunda]

You will avoid confusion if K (1024) is used only in the context of counting information. For example, if you buy a 8 GB flash drive, you can be assured that it is an integer multiple of 1024 bytes. As far as I know, the SI system of units does not even address counting information, nor numbering systems other than base 10.

K (1024) should never be used for things like length in meters.

In natural language, we have homonyms. Words with different meanings that sound alike. In this case, K (1024) and k (1000) are like homonyms. It is up to all of us to keep them separate.

 

[DrClaude]

As far as I know, the SI system of units does not even address counting information, nor numbering systems other than base 10.

Indeed:

These SI prefixes refer strictly to powers of 10. They should not be used to indicate powers of 2 (for example, one kilobit represents 1000 bits and not 1024 bits). The IEC has adopted prefixes for binary powers in the international standard IEC 60027-2: 2005, third edition, Letter symbols to be used in electrical technology – Part 2: Telecommunications and electronics.

[...]

Although these prefixes are not part of the SI, they should be used in the field of information technology to avoid the incorrect usage of the SI prefixes.

 

[stefan r]

The Metre Convention was prejudiced. Full of speciests. Every one of the delegates came from a species with 10 fingers. There are alternatives that are much simpler and are easy to convert to binary:

With a hexadecimal number system:
Kilo = 2^A = 400
Mega =2¹⁴ = 100,000
Giga = 2^1E = 40,000,000

In octal:
Kilo =2¹²=2,000
Mega = 2²⁴ = 4,000,000
Giga = 2³⁶=10,000,000,000

 

[A.T.]

Is this true or not?

Conventions are neither. They can be useful or not.