Notices Federal Register Vol: Fill & Download for Free

“Which is more accurate in measurement; pound or kilogram?”Because the pound is legally (and, therefore, officially) defined in terms of the kilogram as1 lb = 0.453 592 37 kg †that means the pound is an exact fraction of kilogram, and because the kilogram is defined as part of SI, which declares the kilogram to be a unit of mass, so a fraction of an amount of mass must likewise be mass. Therefore, contrary to the claims of the engineers who have responded, the pound is a unit of mass, not force, so values expressed in pounds or kilograms can be freely converted to being expressed in terms of the other unit without any assumptions needed about the strength of gravity or anything else.Because the conversion factor is known exactly, if we know the exact number of pounds for some quantity, we know the exact number of kilograms, and vice versa. If we have a good idea of the uncertainty of our measurement and it is expressed in the same units as our measurement, then we can convert the uncertainty along with the measurement to the other units, and the relative uncertainty (which is the ratio of the uncertainty divided by the measurement value) will be the same, regardless which units of measurement are being used. This is true, no matter how much of the uncertainty is due to systematic bias versus random fluctuations.Therefore, the degree of relative uncertainty for measuring in kilograms versus pounds is the same and cannot be validly used as rationale to choose one unit over the other. (There are other justifications for using kilograms over pounds, but this is not one of them.)Now, not all measurement units are equal in this regard as the kilogram and pound are. Some pairs of units are not defined one in terms of the other (neither directly nor indirectly), but the conversion factor is a measured quantity, which itself has measurement uncertainty. In such cases measuring in one unit and converting to another unit increases the amount of relative uncertainty on top of the relative uncertainty of the original measurement. An example of this situation is the pair of mass units kilogram and dalton. The kilogram can be used to measure the mass of things large and small. The dalton is intended specifically for small objects like individual atoms and molecules; it is defined to be 1/12 of the mass of one free, ground state carbon-12 atom. It is relatively very easy to measure the mass of one atom or molecule relative to a carbon-12 atom with very good accuracy and precision. It is harder to measure an atom or molecule relative to the kilogram. Therefore, measuring the mass of atoms and molecules in terms of daltons has better accuracy and precision than measuring its mass in terms of kilograms, regardless whether you measure directly in terms of kilograms or measure in dalton's and convert to kilograms. The reverse situation applies for the mass of every day objects.† NOTE: This definition of the pound, established 1959-07-01, was made official for the US by a notice published in the Federal Register Vol. 24, #128, p. 5348. From 1893 to 1959, slightly differing fractions of the kilogram were used to define the pound.

Donald Trump may not accept a “gift”.But this does not mean the President can not accept a gift.There is an office in the Government to handle these things.Why would things be any different now?Just for giggles let’s see what the last administration got in gifts for the last year;Federal Register / Vol. 81, No. 197 / Wednesday, October 12, 2016 / Notices 70493The Honorable Barack Obama, President of the United States. Sterling silver sphere that opens to display a clock under a magnifying glass on a wooden pedestal. Rec’d—5/14/2015. Est. Value—$10,064.00. Disposition —National Archives and Records Administration. His Royal Highness Salman Bin Hamad Al Khalifa, Crown Prince of the Kingdom of Bahrain. Non-acceptance would cause embarrassment to donor and U.S. Government. The Honorable Barack Obama, President of the United States. 31″ x 42″ framed pencil sketch portrait of President Obama. Rec’d—5/14/2015. Est. Value— $550.00. Disposition—National Archives and Records Administration.. His Excellency Lieutenant General Dr. Seretse Khama Ian Khama, President of the Republic of Botswana. Non-acceptance would cause embarrassment to donor and U.S. Government. The Honorable Barack Obama, President of the United States. 9″ gold-plated mechanical bird of a Common Chiffchaff that tweets, turns, and flaps its wings once per hour. Rec’d—5/ 14/2015. Est. Value— $110,000.00. Disposition—National Archives and Records Administration. His Highness Sheikh Tamim bin Hamad Al Thani, Emir of the State of Qatar. Non-acceptance would cause embarrassment to donor and U.S. Government. The Honorable Barack Obama, President of the United States. 12″ miniature replica palm tree made of silver filigree on a marble base. Rec’d—5/21/2015. Est. Value—$1,900.00. Disposition—National Achives and Records Administration. His Excellency Beji Caid Essebsi, President of the Republic of Tunisia. Non-acceptance would cause embarrassment to donor and U.S. Government. The Honorable Barack Obama, President of the United States. Personalized bicycle made of black metal with bell. 10″ x 12″ framed inscribed photograph of the King and Queen of the Netherlands. Rec’d—5/31/2015. Est. Value—$1,600.00. Disposition—National Archives and Records Administration. His Majesty King Willem-Alexander, King of the Netherlands. Non-acceptance would cause embarrassment to donor and U.S. Government. The Honorable Barack Obama, President of the United States. Gold-tone cufflinks engraved with Bavarian coat of arms. 20″ carved wooden statue of a barefoot man with a walking stick and red satchel. Trekking poles with wristbands attached at the top. Black traditional Bavarian jacket with green collar. Brown leather hiking boots. Black hiking socks. Rec’d—6/7/ 2015. Est. Value—$1,928.71. Disposition—National Archives and Records Administration. His Excellency Horst Seehofer, Minister-President of Bavaria. Non-acceptance would cause embarrassment to donor and U.S. Government. The Honorable Barack Obama, President of the United States. Ballpoint pen. Silver pocketwatch. USB drive. Rec’d—6/10/2015. Est. Value—$440.99. Disposition—National Archives and Records Administration. USB drive handle pursuant to United States Secret Service policy. Dr. Saleem Al-Jabouri, Speaker of the Council of Representatives of the Republic of Iraq. Non-acceptance would cause embarrassment to donor and U.S. Government. The Honorable Barack Obama, President of the United States. Warm-up jacket for the Brazil Olympic Team. Rio 2016 white t-shirt. Book set of Brazilian classic literature in green leather-bound volumes. Silvertone cufflinks. Rec’d—6/30/2015. Est. Value—$695.50. Disposition—National Archives and Records Administration.This is just one page. The report for 2015 runs from page 70490 through page 70501, just for the first family.https://www.state.gov/documents/organization/263401.pdf

“How do I convert lbm (pound mass) to lb (pound)?”There is nothing to convert because they are synonymous, and the “m” in “lbm” is redundant.Legally the pound is defined as 1 lb = 0.453 592 37 kg. [This definition was put into place 1959–07–01 by what was then the National Bureau of Standards, now the National Institute of Standards and Technology, as previously agreed to by the directors of the national laboratories of Australia, Canada, New Zealand, South Africa, UK, and USA to resolve disagreements among preceding definitions by those countries. The mechanism by which NIST announces changes to definitions of measurement units is by publishing a notice approved and signed by the director of the Department of Commerce. This particular redefinition was published in the Federal Register Vol.24, #128 (https://cdn.loc.gov/service/ll/fedreg/fr024/fr024128/fr024128.pdf) on page 5348 (the 22nd page of the pdf file) under Announcement near the bottom of the first column, along with a similar redefinition of the yard. Both redefinitions are still in effect.] Did you see that period/full stopright after the “kg”? That is the end of the complete definition. There is nothing about sea level, nothing about Earth’s surface, nothing about the acceleration due to gravity, no caveats, no exceptions. The pound is a fraction of a kilogram, so they must be of the same kind of quantity. The CGPM and BIPM have been very clear regarding what kind of quantity the kilogram is. The kilogram is always to be regarded as a unit of mass, never force; the newton is the coherent unit of force in SI and it is completely different from the kilogram. The definition of the newton makes use of the kilogram, but it also makes use of the meter and the second. People who make up and use a unit called the kilogram-force with symbol kgf are in violation of SI and the metric system.Therefore, the pound must be a unit of mass, not of force.The US, UK, and Canada should do with the pound what has been done with the kilogram—prohibit the use of pound-force (lbf), but, alas, they have not and we are stuck with the consequent confusion of mass versus force, as evidenced by:Paul Hanlon’s answer to the question that has two egregious errors: (1) Conceptually, mass and force are two completely different kinds of quantities and a measure of mass cannot ever be equal to a measure of force, no matter the location. (2) Computationally, on Earth one pound, as a quantity of mass, is attracted to Earth with a force of approximately (within about 0.5 %) one pound-force, not 32 pounds-force (but it is about 32 poundals, a completely different unit from pounds-force).Cosmo Furr’s answer to this question that also has two errors: (1) Conceptually, referring to the “difference between mass and weight” instead of the “difference between mass and force” fails to recognize that “weight” takes on different meanings in different contexts, so that in the context of physics and engineering “weight” has a ~320 year old meaning in English of being a gravitational force between a celestial body and an object (with nonzero mass) near that body versus in the context of commerce, trade, and law “weight” has an over 1000 year old meaning as the result of measuring a quantity of goods using a two-pan balance, a device that quantitatively measures the quantity of matter that the physicists and engineers refer to as mass, and a two-pan balance cannot quantitatively measure force. (2) Conceptually, it is not clear what “baselines” is intended to mean, but physicists and engineers came up with the idea of referring to the amount of force needed to lift a one pound object off the surface of Earth is approximately one pound-force as a convenient computational coupling between amount of mass of an object and amount of gravitational force on that object near Earth’s surface, which is the context that most people need to know that coupling relationship most of the time, so there is no “just happens” about it—it was very deliberate.[NOTE: All numbers given in equations in the discussion are exact unless trailed by a “…”.]In case you are wondering about the pound-force as a unit of force, it roughly corresponds to the force by Earth’s gravity on an object of mass 1 lb at sea level near 45° latitude. The actual the actual definition is:[math]1\text{ lbf} = (1\text{ lb}) × g{_\text{n}}[/math],where [math]g{_\text{n}}[/math] is the nominal acceleration due to gravity:[math]g{_\text{n}} = 9.806\,65\text{ m s}^{-2}[/math].(Yes, the relationship between the pound and the pound-force, a pair of USA/UK units is defined in terms of a metric expression—I love it!)[math]Now, 1\text{ ft} = \frac{1}{3}\text{ yd} = \frac{1}{3}(0.9144\text{ m}) = 0.3048\text{ m}[/math].The 0.9144 factor comes from the same Federal Register notice.Therefore,[math]g_{\text{n}} = 9.806\,65\text{ m s}^{-2} = 9.806\,65 × \frac{1}{0.3048}\text{ ft s}^{-2} = 32.174\,048\,556…\text{ ft s}^{-2}[/math],so that:[math]1\text{ lbf} = (1\text{ lb}) × 32.174\,048\,556…\text{ ft s}^{-2} = 32.174\,048\,556…\text{ lb ft s}^{-2}[/math].Now, the unit of force poundal (symbol pdl) is the coherent unit of force in the USA/UK foot-pound-second system and is defined to be:[math]1\text{ pdl} = 1\text{ lb ft s}^{-2}[/math].Therefore,[math]1\text{ lbf} = 32.174\,048\,556…\text{ pdl}[/math].The pound-force can be defined also in terms of SI units. Because 1 lb = 0.453 592 37 kg, we have:[math]1\text{ lbf} = (1\text{ lb}) × g{_\text{n}} = 0.453\,592\,37\text{ kg} × 9.806\,65\text{ m s}^{-2}[/math][math] = 4.448\,221\,615\,260\,5\text{ kg m s}^{-2} = 4.448\,221\,615\,260\,5\text{ N}[/math].The pound-force can be used for any kind of force (though I would advise using SI units instead)—gravitational, spring, tension, electric, magnetic, pressure-induced, …—not just gravitational. If one is dealing with gravitational force acting on an object on the surface of Earth (defining gravitational force as the weight force by an object on a firm horizontal surface fixed to the Earth), then a object of mass n lb encounters a gravitational force of m lbf, where the number m is within 0.5 % of the value n. That 0.5 % is an upper bound on the deviations away from nominal in Earth’s gravity over its surface, including effects of latitude, elevation, and variations in mass concentration, which is why some engineers like using pounds for mass and pounds-force for force, even though it can be confusing at times to keep straight when mass is being discussed versus when force is being discussed; m = n if and only if the acceleration due to gravity at the locale of concern is exactly the nominal [math]9.806\,65\text{ m s}^{-2}[/math]. For any other forces or conditions (accelerating in an elevator, orbiting Earth in a spacecraft, being on some celestial body other than Earth, or application of any non-gravitational force), the relationship between the number of pounds of mass of an object and the number of pound-force of net force on that object is pretty much arbitrary, and information about the conditions and situation is required.[NOTE: When we refer to the acceleration due to gravity and gravitational force, we should realize that this is an oversimplification of terminology. We usually discuss these concepts in the context of Earth, which is rotating and, therefore, is not an inertial frame. The acceleration due to gravity is always discussed and measured on Earth from the perspective of the non-inertial frame that we are in, so that what we would realize from the viewpoint of an inertial frame as a centripetal acceleration due to rotation, everything is flipped from our non-inertial perspective so we sense a centrifugal acceleration that partially offsets the actual gravitational attraction, making the apparent acceleration due to gravity less than the actual.]