this post was submitted on 07 Mar 2024
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Hatzegopteryx (mander.xyz)
submitted 6 months ago by [email protected] to c/[email protected]
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[–] [email protected] 7 points 6 months ago (2 children)

We are not talking about the weight force here. We are simply converting pounds-mass to kg. If you dont believe OP meant the mass (whicg Im sure he certainly did) then aks him but when saying something weighs a certain amount then one is usually referring to its mass.

[–] [email protected] 1 points 6 months ago (2 children)

We were actually talking about Force, though. Pounds is a force, not a mass. I am OP and I meant force because I'm assuming the animal lived on earth. If I wanted to specify mass then I would have used Slugs, the Imperial unit for Mass.

[–] [email protected] 1 points 6 months ago* (last edited 6 months ago) (1 children)

Could you provide any source that states that a pound is a unit of force? Because the American National Standard Institute (here), aswell as Wikipedia and numerous other sources claim its a unit of mass.

[–] [email protected] 1 points 6 months ago (2 children)

The article you linked to does not mention at any point that LBS is a mass, or at all uses the word mass at any point throughout. In fact, it breifly at the end mentions "1 lb=0.45359237 kilogram" as well as "1 Newton=0.224809 pound force" which could indicate a difference between LBF and LBM distinctions.

It's commonly understood that you will weigh a different amount of lbs on the moon than on earth. Because it isn't a mass. It's a force of gravity.

There is also evidence in the form of lbs/in^2 being a common measurement, which would be completely nonsense in the context of mass.

[–] [email protected] 2 points 6 months ago* (last edited 6 months ago) (1 children)

I love educational threads like these.

Even though the original point was "using international standard units makes it clearer for everyone"

[–] [email protected] 1 points 6 months ago

Yeah it is pretty fun.

[–] [email protected] 1 points 6 months ago (1 children)

Alright, lets look at the US Customary Units and their definitions. Here is the section called "Mass and Weight". As you can see, everything is defined in metric units of mass. You won't find even pound-force to be part of the Customary units. I couldn't find any source saying that pound (not "pound-force") is a unit of force. However, there was an agreement (I think in 1955) to define the pound in kg.

it breifly at the end mentions "1 lb=0.45359237 kilogram" as well as "1 Newton=0.224809 pound force"

That basically implies that lb (pound, imperial unit) is a unit of mass and "pound-force" (non-imperial unit, part of the British Engineering Units) is a unit of force. Thus, pound (on its own) is a unit of mass, right?

[–] [email protected] 1 points 6 months ago

British Engineering Units are not a part of the US-Imperial System, but since I never specified I suppose it's a good argument.

[–] [email protected] 0 points 6 months ago (1 children)

Did you take into account that earth was heavier millions of years ago? Also, you would have to specify where on earth it weighed that amount.

Anyway, pound is an imperial unit for mass, just like slug. The "pound-force" is not part of the imperial units, jut rather of the "English Engineering Units" that differentiate between pound-mass, pound-force, pound-foot and others.

"Pound" is not a unit of force in ANY system. If you really meant force (I doubt that) you should have used lbf. Anyway, noone cares how many Newtons of force the earth exhibited on that animal, all the metric-using people in this thread are interested in its mass. All scales used to weigh something display kg (or pounds), so units of mass.

[–] [email protected] 1 points 6 months ago (1 children)

The dino would need to be even lighter if the earth was heavier because the force of gravity would be higher, but in general differences in gravity across the earth's surface amounts to a rounding error. For example, you're probably looking at 2000 ish miligal from the top of a tall mountain to sea level difference in gravity, or .02m/s^2 difference.

[–] [email protected] 1 points 6 months ago

From mountain to sea level yeah but the difference between Equator and North Pole is almost 1% because Earth is not a perfect sphere.