On the Terms Mass and Weight
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Appendix A: Symbols and Prefixes
Appendix A: Symbols and Prefixes (Appendix A last revised November 2020) This appendix of the Author's Kit provides recommendations on prefixes, unit symbols and abbreviations, and factors for conversion into units of the International System. Prefixes Recommended prefixes indicating decimal multiples or submultiples of units and their symbols are as follows: Multiple Prefix Abbreviation 1024 yotta Y 1021 zetta Z 1018 exa E 1015 peta P 1012 tera T 109 giga G 106 mega M 103 kilo k 102 hecto h 10 deka da 10-1 deci d 10-2 centi c 10-3 milli m 10-6 micro μ 10-9 nano n 10-12 pico p 10-15 femto f 10-18 atto a 10-21 zepto z 10-24 yocto y Avoid using compound prefixes, such as micromicro for pico and kilomega for giga. The abbreviation of a prefix is considered to be combined with the abbreviation/symbol to which it is directly attached, forming with it a new unit symbol, which can be raised to a positive or negative power and which can be combined with other unit abbreviations/symbols to form abbreviations/symbols for compound units. For example: 1 cm3 = (10-2 m)3 = 10-6 m3 1 μs-1 = (10-6 s)-1 = 106 s-1 1 mm2/s = (10-3 m)2/s = 10-6 m2/s Abbreviations and Symbols Whenever possible, avoid using abbreviations and symbols in paragraph text; however, when it is deemed necessary to use such, define all but the most common at first use. The following is a recommended list of abbreviations/symbols for some important units. -
Guide for the Use of the International System of Units (SI)
Guide for the Use of the International System of Units (SI) m kg s cd SI mol K A NIST Special Publication 811 2008 Edition Ambler Thompson and Barry N. Taylor NIST Special Publication 811 2008 Edition Guide for the Use of the International System of Units (SI) Ambler Thompson Technology Services and Barry N. Taylor Physics Laboratory National Institute of Standards and Technology Gaithersburg, MD 20899 (Supersedes NIST Special Publication 811, 1995 Edition, April 1995) March 2008 U.S. Department of Commerce Carlos M. Gutierrez, Secretary National Institute of Standards and Technology James M. Turner, Acting Director National Institute of Standards and Technology Special Publication 811, 2008 Edition (Supersedes NIST Special Publication 811, April 1995 Edition) Natl. Inst. Stand. Technol. Spec. Publ. 811, 2008 Ed., 85 pages (March 2008; 2nd printing November 2008) CODEN: NSPUE3 Note on 2nd printing: This 2nd printing dated November 2008 of NIST SP811 corrects a number of minor typographical errors present in the 1st printing dated March 2008. Guide for the Use of the International System of Units (SI) Preface The International System of Units, universally abbreviated SI (from the French Le Système International d’Unités), is the modern metric system of measurement. Long the dominant measurement system used in science, the SI is becoming the dominant measurement system used in international commerce. The Omnibus Trade and Competitiveness Act of August 1988 [Public Law (PL) 100-418] changed the name of the National Bureau of Standards (NBS) to the National Institute of Standards and Technology (NIST) and gave to NIST the added task of helping U.S. -
2019 Redefinition of SI Base Units
2019 redefinition of SI base units A redefinition of SI base units is scheduled to come into force on 20 May 2019.[1][2] The kilogram, ampere, kelvin, and mole will then be defined by setting exact numerical values for the Planck constant (h), the elementary electric charge (e), the Boltzmann constant (k), and the Avogadro constant (NA), respectively. The metre and candela are already defined by physical constants, subject to correction to their present definitions. The new definitions aim to improve the SI without changing the size of any units, thus ensuring continuity with existing measurements.[3][4] In November 2018, the 26th General Conference on Weights and Measures (CGPM) unanimously approved these changes,[5][6] which the International Committee for Weights and Measures (CIPM) had proposed earlier that year.[7]:23 The previous major change of the metric system was in 1960 when the International System of Units (SI) was formally published. The SI is a coherent system structured around seven base units whose definitions are unconstrained by that of any other unit and another twenty-two named units derived from these base units. The metre was redefined in terms of the wavelength of a spectral line of a The SI system after the 2019 redefinition: krypton-86 radiation,[Note 1] making it derivable from universal natural Dependence of base unit definitions onphysical constants with fixed numerical values and on other phenomena, but the kilogram remained defined in terms of a physical prototype, base units. leaving it the only artefact upon which the SI unit definitions depend. The metric system was originally conceived as a system of measurement that was derivable from unchanging phenomena,[8] but practical limitations necessitated the use of artefacts (the prototype metre and prototype kilogram) when the metric system was first introduced in France in 1799. -
Arxiv:0801.0028V1 [Physics.Atom-Ph] 29 Dec 2007 § ‡ † (People’S China Metrology, Of) of Lic Institute Canada National Council, Zhang, Research Z
CODATA Recommended Values of the Fundamental Physical Constants: 2006∗ Peter J. Mohr†, Barry N. Taylor‡, and David B. Newell§, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8420, USA (Dated: March 29, 2012) This paper gives the 2006 self-consistent set of values of the basic constants and conversion factors of physics and chemistry recommended by the Committee on Data for Science and Technology (CODATA) for international use. Further, it describes in detail the adjustment of the values of the constants, including the selection of the final set of input data based on the results of least-squares analyses. The 2006 adjustment takes into account the data considered in the 2002 adjustment as well as the data that became available between 31 December 2002, the closing date of that adjustment, and 31 December 2006, the closing date of the new adjustment. The new data have led to a significant reduction in the uncertainties of many recommended values. The 2006 set replaces the previously recommended 2002 CODATA set and may also be found on the World Wide Web at physics.nist.gov/constants. Contents 3. Cyclotron resonance measurement of the electron relative atomic mass Ar(e) 8 Glossary 2 4. Atomic transition frequencies 8 1. Introduction 4 1. Hydrogen and deuterium transition frequencies, the 1. Background 4 Rydberg constant R∞, and the proton and deuteron charge radii R , R 8 2. Time variation of the constants 5 p d 1. Theory relevant to the Rydberg constant 9 3. Outline of paper 5 2. Experiments on hydrogen and deuterium 16 3. -
The International System of Units (SI)
NAT'L INST. OF STAND & TECH NIST National Institute of Standards and Technology Technology Administration, U.S. Department of Commerce NIST Special Publication 330 2001 Edition The International System of Units (SI) 4. Barry N. Taylor, Editor r A o o L57 330 2oOI rhe National Institute of Standards and Technology was established in 1988 by Congress to "assist industry in the development of technology . needed to improve product quality, to modernize manufacturing processes, to ensure product reliability . and to facilitate rapid commercialization ... of products based on new scientific discoveries." NIST, originally founded as the National Bureau of Standards in 1901, works to strengthen U.S. industry's competitiveness; advance science and engineering; and improve public health, safety, and the environment. One of the agency's basic functions is to develop, maintain, and retain custody of the national standards of measurement, and provide the means and methods for comparing standards used in science, engineering, manufacturing, commerce, industry, and education with the standards adopted or recognized by the Federal Government. As an agency of the U.S. Commerce Department's Technology Administration, NIST conducts basic and applied research in the physical sciences and engineering, and develops measurement techniques, test methods, standards, and related services. The Institute does generic and precompetitive work on new and advanced technologies. NIST's research facilities are located at Gaithersburg, MD 20899, and at Boulder, CO 80303. -
Comparing Many-Body Approaches Against the Helium Atom Exact Solution
SciPost Phys. 6, 040 (2019) Comparing many-body approaches against the helium atom exact solution Jing Li1,2, N. D. Drummond3, Peter Schuck1,4,5 and Valerio Olevano1,2,6? 1 Université Grenoble Alpes, 38000 Grenoble, France 2 CNRS, Institut Néel, 38042 Grenoble, France 3 Department of Physics, Lancaster University, Lancaster LA1 4YB, United Kingdom 4 CNRS, LPMMC, 38042 Grenoble, France 5 CNRS, Institut de Physique Nucléaire, IN2P3, Université Paris-Sud, 91406 Orsay, France 6 European Theoretical Spectroscopy Facility (ETSF) ? [email protected] Abstract Over time, many different theories and approaches have been developed to tackle the many-body problem in quantum chemistry, condensed-matter physics, and nuclear physics. Here we use the helium atom, a real system rather than a model, and we use the exact solution of its Schrödinger equation as a benchmark for comparison between methods. We present new results beyond the random-phase approximation (RPA) from a renormalized RPA (r-RPA) in the framework of the self-consistent RPA (SCRPA) originally developed in nuclear physics, and compare them with various other approaches like configuration interaction (CI), quantum Monte Carlo (QMC), time-dependent density- functional theory (TDDFT), and the Bethe-Salpeter equation on top of the GW approx- imation. Most of the calculations are consistently done on the same footing, e.g. using the same basis set, in an effort for a most faithful comparison between methods. Copyright J. Li et al. Received 15-01-2019 This work is licensed under the Creative Commons Accepted 21-03-2019 Check for Attribution 4.0 International License. -
Fundamental Physical Constants — Extensive Listing Relative Std
2018 CODATA adjustment From: http://physics.nist.gov/constants Fundamental Physical Constants — Extensive Listing Relative std. Quantity Symbol Value Unit uncert. ur UNIVERSAL speed of light in vacuum c 299 792 458 m s−1 exact 2 −6 −2 −10 vacuum magnetic permeability 4pα¯h=e c µ0 1:256 637 062 12(19) × 10 NA 1:5 × 10 −7 −2 −10 µ0=(4p × 10 ) 1:000 000 000 55(15) NA 1:5 × 10 2 −12 −1 −10 vacuum electric permittivity 1/µ0c 0 8:854 187 8128(13) × 10 F m 1:5 × 10 −10 characteristic impedance of vacuum µ0c Z0 376:730 313 668(57) Ω 1:5 × 10 Newtonian constant of gravitation G 6:674 30(15) × 10−11 m3 kg−1 s−2 2:2 × 10−5 G=¯hc 6:708 83(15) × 10−39 (GeV=c2)−2 2:2 × 10−5 Planck constant∗ h 6:626 070 15 × 10−34 J Hz−1 exact 4:135 667 696 ::: × 10−15 eV Hz−1 exact ¯h 1:054 571 817 ::: × 10−34 J s exact 6:582 119 569 ::: × 10−16 eV s exact ¯hc 197:326 980 4 ::: MeV fm exact 1=2 −8 −5 Planck mass (¯hc=G) mP 2:176 434(24) × 10 kg 1:1 × 10 2 19 −5 energy equivalent mPc 1:220 890(14) × 10 GeV 1:1 × 10 5 1=2 32 −5 Planck temperature (¯hc =G) =k TP 1:416 784(16) × 10 K 1:1 × 10 3 1=2 −35 −5 Planck length ¯h=mPc = (¯hG=c ) lP 1:616 255(18) × 10 m 1:1 × 10 5 1=2 −44 −5 Planck time lP=c = (¯hG=c ) tP 5:391 247(60) × 10 s 1:1 × 10 ELECTROMAGNETIC elementary charge e 1:602 176 634 × 10−19 C exact e=¯h 1:519 267 447 ::: × 1015 AJ−1 exact −15 magnetic flux quantum 2p¯h=(2e) Φ0 2:067 833 848 ::: × 10 Wb exact 2 −5 conductance quantum 2e =2p¯h G0 7:748 091 729 ::: × 10 S exact −1 inverse of conductance quantum G0 12 906:403 72 ::: Ω exact 9 −1 Josephson constant 2e=h -
Introduction to Numerical Projects Format for Electronic Delivery Of
Introduction to numerical projects Here follows a brief recipe and recommendation on how to write a report for each project. • Give a short description of the nature of the problem and the eventual numerical methods you have used. • Describe the algorithm you have used and/or developed. Here you may find it con- venient to use pseudocoding. In many cases you can describe the algorithm in the program itself. • Include the source code of your program. Comment your program properly. • If possible, try to find analytic solutions, or known limits in order to test your program when developing the code. • Include your results either in figure form or in a table. Remember to label your results. All tables and figures should have relevant captions and labels on the axes. • Try to evaluate the reliabilty and numerical stability/precision of your results. If pos- sible, include a qualitative and/or quantitative discussion of the numerical stability, eventual loss of precision etc. • Try to give an interpretation of you results in your answers to the problems. • Critique: if possible include your comments and reflections about the exercise, whether you felt you learnt something, ideas for improvements and other thoughts you’ve made when solving the exercise. We wish to keep this course at the interactive level and your comments can help us improve it. We do appreciate your comments. • Try to establish a practice where you log your work at the computerlab. You may find such a logbook very handy at later stages in your work, especially when you don’t properly remember what a previous test version of your program did. -
Photoelectric Effect Prac
Name ___________________. Photoelectric Effect Prac 1. The threshold frequency in a photoelectric experiment is most closely related to the A) brightness of the incident light B) thickness of the photoemissive metal C) area of the photoemissive metal D) work function of the photoemissive metal 2. When a source of dim orange light shines on a photosensitive metal, no photoelectrons are ejected from its surface. What could be done to increase the likelihood of producing photoelectrons? A) Replace the orange light source with a red light source. B) Replace the orange light source with a higher frequency light source. C) Increase the brightness of the orange light source. D) Increase the angle at which the photons of orange light strike the metal. 3. The threshold frequency for a photoemissive surface is hertz. Which color light, if incident upon the surface, may produce photoelectrons? A) blue B) green C) yellow D) red 4. The threshold frequency of a metal surface is in the violet light region. What type of radiation will cause photoelectrons to be emitted from the metal's surface? A) infrared light B) red light C) ultraviolet light D) radio waves 5. Photons with an energy of 7.9 electron-volts strike a zinc plate, causing the emission of photoelectrons with a maximum kinetic energy of 4.0 electronvolts. The work function of the zinc plate is A) 11.9 eV B) 7.9 eV C) 3.9 eV D) 4.0 eV 6. The threshold frequency for a photoemissive surface is 1.0 × 1014 hertz. What is the work function of the surface? A) 1.0 × 10–14 J B) 6.6 × 10–20 J C) 6.6 × 10–48 J D) 2.2 × 10–28 J 7. -
9081872 Physics Jan. 01
The University of the State of New York REGENTS HIGH SCHOOL EXAMINATION PHYSICS Tuesday, January 23, 2001 — 9:15 a.m. to 12:15 p.m., only The answer paper is stapled in the center of this examination booklet. Open the examination book- let, carefully remove the answer paper, and close the examination booklet. Then fill in the heading on your answer paper. All of your answers are to be recorded on the separate answer paper. For each question in Part I and Part II, decide which of the choices given is the best answer. Then on the answer paper, in the row of numbers for that question, circle with pencil the number of the choice that you have selected. The sample below is an example of the first step in recording your answers. SAMPLE: 1 2 3 4 If you wish to change an answer, erase your first penciled circle and then circle with pencil the num- ber of the answer you want. After you have completed the examination and you have decided that all of the circled answers represent your best judgment, signal a proctor and turn in all examination material except your answer paper. Then and only then, place an X in ink in each penciled circle. Be sure to mark only one answer with an X in ink for each question. No credit will be given for any question with two or more X’s marked. The sample below indicates how your final choice should be marked with an X in ink. SAMPLE: 1 2 3 4 For questions in Part III, record your answers in accordance with the directions given in the exami- nation booklet. -
Molar Mass 1 Molar Mass
Molar mass 1 Molar mass In chemistry, the molar mass is a physical property. It is defined as the mass of a given substance (chemical element or chemical compound) divided by its amount of substance. The base SI unit for molar mass is kg/mol. However, for historical reasons, molar masses are almost always expressed in g/mol. As an example, the molar mass of water is approximately: M(H O) ≈ 18 g⋅mol−1 2 Molar masses of elements The molar mass of atoms of an element is given by the atomic mass of the element multiplied by the molar mass constant, M −3 u = 1×10 kg/mol = 1 g/mol: M(H) = 1.007 97(7) × 1 g/mol = 1.007 97(7) g/mol M(S) = 32.065(5) × 1 g/mol = 32.065(5) g/mol M(Cl) = 35.453(2) × 1 g/mol = 35.453(2) g/mol M(Fe) = 55.845(2) × 1 g/mol = 55.845(2) g/mol. Multiplying by the molar mass constant ensures that the calculation is dimensionally correct: atomic weights are dimensionless quantities (i.e., pure numbers) whereas molar masses have units (in this case, grams/mole). Some elements are usually encountered as molecules, e.g. hydrogen (H 2), sulfur (S 8), chlorine (Cl 2). The molar mass of molecules of these elements is the molar mass of the atoms multiplied by the number of atoms in each molecule: M(H 2) = 2 × 1.007 97(7) × 1 g/mol = 2.015 88(14) g/mol M(S 8) = 8 × 32.065(5) × 1 g/mol = 256.52(4) g/mol M(Cl 2) = 2 × 35.453(2) × 1 g/mol = 70.906(4) g/mol. -
Sievert to Rem Conversion Table
Sievert To Rem Conversion Table Jerrome remains repeatable after Galen unthaw robustiously or equilibrated any savagery. Tribadic disemboguesTheophyllus dehydrate so uninterruptedly. mentally while Grained Elihu Kingsley always dispeopledquakings his exemplarily. Grappelli merged errantly, he Gray conversion table above, sieverts rems are not necessary between sievert is that all premises and gamma rays being required in. How is radiation measured? Table 4 summarizes the units used for measuring radiation. Table B6 includes selected conversions from rem to sievert Table B6 Radiological. Bq per kilogram of meat is a large raise and consequently considered to be dangerous. All across our conventional units to rem conversion table below shows that work where accumulated radiation dose even when i can it? The units of dose equivalent are the sievert Sv and the rem. What is radiation exposure? Jerry, but a small error. Equivalent dose can be seen as an intermediate step in the calculation of effective dose. Internationale d'units the corresponding non-SI units their symbols and the conversion factors Table 3 Units of Radioactivity and Radiation Dose Quantity SI unit office symbol. When you are converting equivalent dose, you need a Röntgen Equivalent Man to Sievert converter that is elaborate and still easy to use. Sievert to Rem Conversion Nuclear Power Plants World Wide. National Academies of Sciences, Engineering, and Medicine. Radiation Converter Omni Calculator. Equivalent in rem conversion table gives you wish to sievert to rem conversion table shows the sievert. Do to sievert rem conversion table shows the table. We use sv, and their associated with a vital role in this is, or photons that you are likely candidate for.