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cowboyro
Premium
join:2000-10-11
Shelton, CT
reply to InvalidError

Re: Weights and measures

said by InvalidError:

The difference is that weights, volumes, lengths, etc. are physical measurements that can vary with temperature, humidity, physical wear,

No they don't. A kilogram is a kilogram, whether on the Earth at the North Pole or on the bright side of the moon. Same for a meter, same for a liter.
said by InvalidError:

Another possibility is your IP address getting spammed by portscans and other activities which AT&T cannot really tell apart from regular traffic in which case the only way to avoid it is to turn off the modem when not in use.

With Uverse, modem off means no TV. Not even being able to watch already recorded shows...


88615298
Premium
join:2004-07-28
West Tenness

said by cowboyro:

No they don't. A kilogram is a kilogram, whether on the Earth at the North Pole or on the bright side of the moon. Same for a meter, same for a liter.

Actually the moon's gravity is 1/6 that of Earth so a kilogram on Earth would be 1/6 kilogram on the moon.

Also technically gravity is slightly stronger at the north pole so a kilogram at the equator would be slightly more than a kilogram at the north pole.

Petermjjh

join:2005-04-03
Bloomfield Hills, MI

Re: 50Mb vs 105Mb technical/install differences?

Nope a kilogram is a kilogram no matter what.

However acceleration due to gravity is different on the moon than on Earth. You are thinking of weight which is measured in Kg m/s2, or a Newton (N).


InvalidError

join:2008-02-03
kudos:5
reply to cowboyro

Re: Weights and measures

said by cowboyro:

No they don't. A kilogram is a kilogram, whether on the Earth at the North Pole or on the bright side of the moon. Same for a meter, same for a liter.

A kilogram may be a kilogram and a liter may be a liter but the calibration of measurement instruments can drift over time due to temperature, humidity, wear, aging, corrosion, contamination, etc.

This is why physical quantity measurement equipment needs to be periodically inspected and calibrated.

darkcrucible

join:2007-06-07
kudos:1

1 recommendation

reply to 88615298

This is not correct. A kilogram is a measurement of mass. That is, how much stuff there is in something. A kilogram of carbon will still be a kilogram on the moon, the north pole or anywhere else. What you're thinking of is weight which is not the same as mass.

For example, there are 6.03x10^23 atoms of carbon in 12 grams of carbon. Just because you take that carbon to the moon doesn't suddenly mean there are 1.005x10^23 atoms of carbon (2 gram of C).



cowboyro
Premium
join:2000-10-11
Shelton, CT
reply to 88615298

said by 88615298:

said by cowboyro:

No they don't. A kilogram is a kilogram, whether on the Earth at the North Pole or on the bright side of the moon. Same for a meter, same for a liter.

Actually the moon's gravity is 1/6 that of Earth so a kilogram on Earth would be 1/6 kilogram on the moon.

Also technically gravity is slightly stronger at the north pole so a kilogram at the equator would be slightly more than a kilogram at the north pole.

The mass is a property of an object. It does not change.(*)
Weight on the other side is the force exerted by gravitation. We conveniently refer to mass as weight as on Earth the difference is negligible for most practical purposes. We are actually measuring the weight force and translating into "the mass that produces the weight on Earth".
-----
(*)exception for objects that absorb or release energy in nuclear fusion or fission reactions.

prairiesky

join:2008-12-08
canada
kudos:2
reply to 88615298

said by 88615298:

said by cowboyro:

No they don't. A kilogram is a kilogram, whether on the Earth at the North Pole or on the bright side of the moon. Same for a meter, same for a liter.

Actually the moon's gravity is 1/6 that of Earth so a kilogram on Earth would be 1/6 kilogram on the moon.

Also technically gravity is slightly stronger at the north pole so a kilogram at the equator would be slightly more than a kilogram at the north pole.

??
You're confusing lbs with KG, kg's don't change as a result of gravity.

Data is completely different. Data is simply a count. Like, I have 3 apples. All of our measuring devices are subject to physical variations such as temperatures, pressures etc. The units are also defined by substances, for instance, 1 KG is 1 L of water. 1 L doesn't change based on external forces, but the amount of water contained within that space sure does hence the definition of 1 KG being 1 L / water needs contraints on the variables that affect it.

Data is simply a count. I transfered 3 apples, either you did or you didn't, there are no external forces that change that count. it's either right or it's wrong


koolman2
Premium
join:2002-10-01
Anchorage, AK

Pounds and grams both measure the same thing: mass. 5 kg = 11.023 lbs on Earth as well as the moon.



arandomguy

@suddenlink.net

Nope. Grams and their variants are a measure of the amount of mass an object has. Pounds is a measure of the force of gravity over an object. An object will weigh less on the moon, but will still have the same mass. Does no one take science class these days?


prairiesky

join:2008-12-08
canada
kudos:2
reply to koolman2

there is a mass pound, but the general term lb/pound refers to a weight, which is a force not a mass. Because the mass pound and the force pound (weight) are so closely labeled, Grams are much preferred for use of mass.



cowboyro
Premium
join:2000-10-11
Shelton, CT

said by prairiesky:

there is a mass pound, but the general term lb/pound refers to a weight, which is a force not a mass.

No they are not.
lbs are imperial units for mass, kilograms are [SI] units for mass.


DataRiker
Premium
join:2002-05-19
00000

1 edit
reply to 88615298

said by 88615298:

Actually the moon's gravity is 1/6 that of Earth so a kilogram on Earth would be 1/6 kilogram on the moon.

Also technically gravity is slightly stronger at the north pole so a kilogram at the equator would be slightly more than a kilogram at the north pole.

You don't even know the first grade definition of mass....


BonezX
Basement Dweller
Premium
join:2004-04-13
Canada
kudos:1

2 edits
reply to 88615298

said by 88615298:

said by cowboyro:

No they don't. A kilogram is a kilogram, whether on the Earth at the North Pole or on the bright side of the moon. Same for a meter, same for a liter.

Actually the moon's gravity is 1/6 that of Earth so a kilogram on Earth would be 1/6 kilogram on the moon.

i love when people apply Imperial theory to SI units, it just makes my day.

an LB is a force(F=M*A), not a mass, weight is a measurement of force, a slug is a mass not a force
a Newton is a force, not a mass, a kg is a mass not a force.

gravity is calculated at 9.8m/s^2, or 32.15ft/s^2

Imperial units are arbitrary, where SI units are standardized.

good example, a meter is how long it takes for light to travel in 1/299 792 458 of a second.


cowboyro
Premium
join:2000-10-11
Shelton, CT

said by BonezX:

i love when people apply Imperial theory to SI units, it just makes my day.
an LB is a force

Actually a lb is a unit for MASS not for force.
1lb is defined as 0.45359237 kilograms.
said by BonezX:

Imperial units are arbitrary, where SI units are standardized.

They are not arbitrary at all. Not any more than SI units. There is a strong, well-defined relationship between imperial and SI units.


DataRiker
Premium
join:2002-05-19
00000

2 edits

The term pound can refer to a mass or a force. The unqualified term "pound" is ambiguous.

If one wishes to be unambiguous you can refer to either a pound-mass or pound-force.

Or just use the SI units since they are designed to be unambiguous.



cowboyro
Premium
join:2000-10-11
Shelton, CT

said by DataRiker:

Since the term pound is unqualified it can refer to a mass or a force.

The term pound denotes a mass (when we are talking about "weights"). The pound-force term denotes the gravitational force exerted by a 1lb mass on Earth.


DataRiker
Premium
join:2002-05-19
00000

4 edits

Weight is a force, so if your going to use some subjective context for reference (which is unwise) lb force would be more fitting.

Since neither of you used "pound-force" [lbf] or "pound-mass" [lbm], any argument that one definition is more correct than the other is extremely silly.

The unqualified "pound" should never ever be used in anything but the most informal oral conversations.



BonezX
Basement Dweller
Premium
join:2004-04-13
Canada
kudos:1
reply to cowboyro

said by cowboyro:

said by DataRiker:

Since the term pound is unqualified it can refer to a mass or a force.

The term pound denotes a mass (when we are talking about "weights"). The pound-force term denotes the gravitational force exerted by a 1lb mass on Earth.

LB is a measurement of force(weight is called the normal force of an object fyi), the imperial measurement of mass is the slug.


cowboyro
Premium
join:2000-10-11
Shelton, CT

said by BonezX:

said by cowboyro:

said by DataRiker:

Since the term pound is unqualified it can refer to a mass or a force.

The term pound denotes a mass (when we are talking about "weights"). The pound-force term denotes the gravitational force exerted by a 1lb mass on Earth.

LB is a measurement of force(weight is called the normal force of an object fyi), the imperial measurement of mass is the slug.

According to NIST it's officially defined as a unit of mass. What some people use it as has no bearing over the official definition.


BonezX
Basement Dweller
Premium
join:2004-04-13
Canada
kudos:1

said by cowboyro:

According to NIST it's officially defined as a unit of mass. What some people use it as has no bearing over the official definition.

»en.wikipedia.org/wiki/Slug_%28mass%29
»en.wikipedia.org/wiki/Normal_force

might want to also look outside the united states of stuck in the past, if you did calculations in the scientific community, or about ~90% of the countries in the world in lb you would be laughed at.


OldCableGuy

@planetcr.net
reply to BonezX

>good example, a meter is how long it takes for light to travel in 1/299 792 458 of a second.

Yeah, that doesn't sound arbitrary or anything.



DataRiker
Premium
join:2002-05-19
00000

3 edits
reply to cowboyro

said by cowboyro:

According to NIST it's officially defined as a unit of mass. What some people use it as has no bearing over the official definition.

This is a rather silly point since force is defined using mass.

When you understand your circular reasoning get back to me.


cowboyro
Premium
join:2000-10-11
Shelton, CT
reply to BonezX

said by BonezX:

said by cowboyro:

According to NIST it's officially defined as a unit of mass. What some people use it as has no bearing over the official definition.

»en.wikipedia.org/wiki/Slug_%28mass%29
»en.wikipedia.org/wiki/Normal_force

might want to also look outside the united states of stuck in the past, if you did calculations in the scientific community, or about ~90% of the countries in the world in lb you would be laughed at.

The pound is the official unit for mass. Not force, mass.
The slug is a derived unit that makes the 1:1 translation between units of time, length and force so that F=m*a


DataRiker
Premium
join:2002-05-19
00000

4 edits

Force is defined using mass.

If you use pound in science, you will be immediately asked to clarify if you mean force or mass.



DataRiker
Premium
join:2002-05-19
00000
reply to OldCableGuy

it is arbitrary until you once again qualify "in a vacuum"

Science is very particular about details