• Aux@lemmy.world
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    8 months ago

    Weight is a force and it’s not mass. Weight is measured in Newtons.

    • HopFlop@discuss.tchncs.de
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      8 months ago

      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.

        • HopFlop@discuss.tchncs.de
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          8 months ago

          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.

            • lightnegative@lemmy.world
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              8 months ago

              I love educational threads like these.

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

            • HopFlop@discuss.tchncs.de
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              8 months ago

              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?

        • HopFlop@discuss.tchncs.de
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          8 months ago

          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.

      • Aux@lemmy.world
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        8 months ago

        No, we don’t refer to mass when weighing something. Measuring mass is quite hard, measuring weight is simple - just use scales.

        • HopFlop@discuss.tchncs.de
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          8 months ago

          In both the British Imperial System and the US Customary Units, a pound is a unit of mass, defined as 0.45359237 kg. In fact, all the definitions in the section “Weights and Masses” of the US Cusomaries are defined in either kg, g or mg.

          • Buffaloaf@lemmy.world
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            8 months ago

            A pound is a unit of force, slug is mass. There’s also lbm (pound-mass) which is what I think you’re thinking of, but that’s not the standard

            • HopFlop@discuss.tchncs.de
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              8 months ago

              A pound is actually not a unit of force. At least not in the US Customary System nor in the British Imperial System. They both are defined as units of mass. Both systems define the standard pound as the “avoirdupois pound”, a unit of mass. The US Customary System doesnt even include a unit of force.

              “Pound-mass” comes from the “English Engineering Units” which differentiates between pounds-mass and pounds-force.

              “Pound” is not a unit of force in any current system. Its the standard unit of mass (slug is also a unit of mass but usually not used). Feel free to provide any source that states that pound is a unit of force.

        • Zacryon@feddit.de
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          8 months ago

          If you use a scale, the force acting upon the mass is calculated out such that you get a mass displayed.

    • Zerush@lemmy.ml
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      8 months ago

      Agree. The error is in the imperial system, there isn’t a difference between weight and mass. The Weight depends on the gravity but the mass not. 240 Pounds Weight on Earth are on the Moon 40 Pounds Weight, but the Mass is still 240 Pound. Because of this in the SI system for the Mass is used kilogramm and for the Weight Newton (old kilopond)