Appendix: a List of Named Units
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M Motion Intervention Booklet.Pdf (810.7KB)
Motion Intervention Booklet 1 Random uncertainties have no pattern. They can cause a reading to be higher or lower than the “true value”. Systematic uncertainties have a pattern. They cause readings to be consistently too high or consistently too low. 2 The uncertainty in repeat readings is found from “half the range” and is given to 1 significant figure. Time / s Trial 1 Trial 2 Trial 3 Mean 1.23 1.20 1.28 Mean time = 1.23 + 1.20 + 1.28 = 1.23666666 => 1.24 (original data is to 2dp, so 3 the mean is to 2 dp as well) Range = 1.20 1.28. Uncertainty is ½ × (1.28 – 1.20) = ½ × 0.08 = ± 0.04 s 3 The speed at which a person can walk, run or cycle depends on many factors including: age, terrain, fitness and distance travelled. The speed of a moving object usually changes while it’s moving. Typical values for speeds may be taken as: walking: 1.5 m/s running: 3 m/s cycling: 6 m/s sound in air: 330 m/s 4 Scalar quantities have magnitude only. Speed is a scaler, eg speed = 30 m/s. Vector quantities have magnitude and direction. Velocity is a vector, eg velocity = 30 m/s north. Distance is how far something moves, it doesn’t involve direction. The displacement at a point is how far something is from the start point, in a straight line, including the direction. It doesn’t make any difference how far the object has moved in order to get to that point. -
Db Math Marco Zennaro Ermanno Pietrosemoli Goals
dB Math Marco Zennaro Ermanno Pietrosemoli Goals ‣ Electromagnetic waves carry power measured in milliwatts. ‣ Decibels (dB) use a relative logarithmic relationship to reduce multiplication to simple addition. ‣ You can simplify common radio calculations by using dBm instead of mW, and dB to represent variations of power. ‣ It is simpler to solve radio calculations in your head by using dB. 2 Power ‣ Any electromagnetic wave carries energy - we can feel that when we enjoy (or suffer from) the warmth of the sun. The amount of energy received in a certain amount of time is called power. ‣ The electric field is measured in V/m (volts per meter), the power contained within it is proportional to the square of the electric field: 2 P ~ E ‣ The unit of power is the watt (W). For wireless work, the milliwatt (mW) is usually a more convenient unit. 3 Gain and Loss ‣ If the amplitude of an electromagnetic wave increases, its power increases. This increase in power is called a gain. ‣ If the amplitude decreases, its power decreases. This decrease in power is called a loss. ‣ When designing communication links, you try to maximize the gains while minimizing any losses. 4 Intro to dB ‣ Decibels are a relative measurement unit unlike the absolute measurement of milliwatts. ‣ The decibel (dB) is 10 times the decimal logarithm of the ratio between two values of a variable. The calculation of decibels uses a logarithm to allow very large or very small relations to be represented with a conveniently small number. ‣ On the logarithmic scale, the reference cannot be zero because the log of zero does not exist! 5 Why do we use dB? ‣ Power does not fade in a linear manner, but inversely as the square of the distance. -
New Realization of the Ohm and Farad Using the NBS Calculable Capacitor
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT, VOL. 38, NO. 2, APRIL 1989 249 New Realization of the Ohm and Farad Using the NBS Calculable Capacitor JOHN Q. SHIELDS, RONALD F. DZIUBA, MEMBER, IEEE,AND HOWARD P. LAYER Abstrucl-Results of a new realization of the ohm and farad using part of the NBS effort. This paper describes our measure- the NBS calculable capacitor and associated apparatus are reported. ments and gives our latest results. The results show that both the NBS representation of the ohm and the NBS representation of the farad are changing with time, cNBSat the rate of -0.054 ppmlyear and FNssat the rate of 0.010 ppm/year. The 11. AC MEASUREMENTS realization of the ohm is of particular significance at this time because The measurement sequence used in the 1974 ohm and of its role in assigning an SI value to the quantized Hall resistance. The farad determinations [2] has been retained in the present estimated uncertainty of the ohm realization is 0.022 ppm (lo) while the estimated uncertainty of the farad realization is 0.014 ppm (la). NBS measurements. A 0.5-pF calculable cross-capacitor is used to measure a transportable 10-pF reference capac- itor which is carried to the laboratory containing the NBS I. INTRODUCTION bank of 10-pF fused silica reference capacitors. A 10: 1 HE NBS REPRESENTATION of the ohm is bridge is used in two stages to measure two 1000-pF ca- T based on the mean resistance of five Thomas-type pacitors which are in turn used as two arms of a special wire-wound resistors maintained in a 25°C oil bath at NBS frequency-dependent bridge for measuring two 100-kQ Gaithersburg, MD. -
Modern Physics Unit 15: Nuclear Structure and Decay Lecture 15.1: Nuclear Characteristics
Modern Physics Unit 15: Nuclear Structure and Decay Lecture 15.1: Nuclear Characteristics Ron Reifenberger Professor of Physics Purdue University 1 Nucleons - the basic building blocks of the nucleus Also written as: 7 3 Li ~10-15 m Examples: A X=Chemical Element Z X Z = number of protons = atomic number 12 A = atomic mass number = Z+N 6 C N= A-Z = number of neutrons 35 17 Cl 2 What is the size of a nucleus? Three possibilities • Range of nuclear force? • Mass radius? • Charge radius? It turns out that for nuclear matter Nuclear force radius ≈ mass radius ≈ charge radius defines nuclear force range defines nuclear surface 3 Nuclear Charge Density The size of the lighter nuclei can be approximated by modeling the nuclear charge density ρ (C/m3): t ≈ 4.4a; a=0.54 fm 90% 10% Usually infer the best values for ρo, R and a for a given nucleus from scattering experiments 4 Nuclear mass density Scattering experiments indicate the nucleus is roughly spherical with a radius given by 1 3 −15 R = RRooA ; =1.07 × 10meters= 1.07 fm = 1.07 fermis A=atomic mass number What is the nuclear mass density of the most common isotope of iron? 56 26 Fe⇒= A56; Z = 26, N = 30 m Am⋅⋅3 Am 33A ⋅ m m ρ = nuc p= p= pp = o 1 33 VR4 3 3 3 44ππA R nuc π R 4(π RAo ) o o 3 3×× 1.66 10−27 kg = 3.2× 1017kg / m 3 4×× 3.14 (1.07 × 10−15m ) 3 The mass density is constant, independent of A! 5 Nuclear mass density for 27Al, 97Mo, 238U (from scattering experiments) (kg/m3) ρo heavy mass nucleus light mass nucleus middle mass nucleus 6 Typical Densities Material Density Helium 0.18 kg/m3 Air (dry) 1.2 kg/m3 Styrofoam ~100 kg/m3 Water 1000 kg/m3 Iron 7870 kg/m3 Lead 11,340 kg/m3 17 3 Nuclear Matter ~10 kg/m 7 Isotopes - same chemical element but different mass (J.J. -
Units and Magnitudes (Lecture Notes)
physics 8.701 topic 2 Frank Wilczek Units and Magnitudes (lecture notes) This lecture has two parts. The first part is mainly a practical guide to the measurement units that dominate the particle physics literature, and culture. The second part is a quasi-philosophical discussion of deep issues around unit systems, including a comparison of atomic, particle ("strong") and Planck units. For a more extended, profound treatment of the second part issues, see arxiv.org/pdf/0708.4361v1.pdf . Because special relativity and quantum mechanics permeate modern particle physics, it is useful to employ units so that c = ħ = 1. In other words, we report velocities as multiples the speed of light c, and actions (or equivalently angular momenta) as multiples of the rationalized Planck's constant ħ, which is the original Planck constant h divided by 2π. 27 August 2013 physics 8.701 topic 2 Frank Wilczek In classical physics one usually keeps separate units for mass, length and time. I invite you to think about why! (I'll give you my take on it later.) To bring out the "dimensional" features of particle physics units without excess baggage, it is helpful to keep track of powers of mass M, length L, and time T without regard to magnitudes, in the form When these are both set equal to 1, the M, L, T system collapses to just one independent dimension. So we can - and usually do - consider everything as having the units of some power of mass. Thus for energy we have while for momentum 27 August 2013 physics 8.701 topic 2 Frank Wilczek and for length so that energy and momentum have the units of mass, while length has the units of inverse mass. -
Decibels, Phons, and Sones
Decibels, Phons, and Sones The rate at which sound energy reaches a Table 1: deciBel Ratings of Several Sounds given cross-sectional area is known as the Sound Source Intensity deciBel sound intensity. There is an abnormally Weakest Sound Heard 1 x 10-12 W/m2 0.0 large range of intensities over which Rustling Leaves 1 x 10-11 W/m2 10.0 humans can hear. Given the large range, it Quiet Library 1 x 10-9 W/m2 30.0 is common to express the sound intensity Average Home 1 x 10-7 W/m2 50.0 using a logarithmic scale known as the Normal Conversation 1 x 10-6 W/m2 60.0 decibel scale. By measuring the intensity -4 2 level of a given sound with a meter, the Phone Dial Tone 1 x 10 W/m 80.0 -3 2 deciBel rating can be determined. Truck Traffic 1 x 10 W/m 90.0 Intensity values and decibel ratings for Chainsaw, 1 m away 1 x 10-1 W/m2 110.0 several sound sources listed in Table 1. The decibel scale and the intensity values it is based on is an objective measure of a sound. While intensities and deciBels (dB) are measurable, the loudness of a sound is subjective. Sound loudness varies from person to person. Furthermore, sounds with equal intensities but different frequencies are perceived by the same person to have unequal loudness. For instance, a 60 dB sound with a frequency of 1000 Hz sounds louder than a 60 dB sound with a frequency of 500 Hz. -
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. -
Comparative Study on the Battery State-Of-Charge Estimation Method
ISSN (Print) : 0974-6846 Indian Journal of Science and Technology, Vol 8(26), DOI: 10.17485/ijst/2015/v8i26/81677, October 2015 ISSN (Online) : 0974-5645 Comparative Study on the Battery State-of-Charge Estimation Method Seonwoo Jeon1, Jae-Jung Yun2 and Sungwoo Bae1* 1Department of Electrical Engineering, Yeungnam University, Gyeongsan, Gyeongbuk, Korea; [email protected] 2Department of Electrical and Electronics Engineering, Daegu University, Gyeongsan, Gyeongbuk, Korea Abstract Accurate SOC (State-of-Charge) estimation has been an important part for all applications including energy storage sys- tems. The accurate SOC estimation protects a battery to be deeply discharged and over-charged. Many studies on SOC battery temperature, the type of battery and the external conditions. Because of these reasons, SOC estimation methods differestimation from methodsbattery applications have been developed such as energy for evaluating storage more system, accurate hybrid SOC electrical value. The vehicle battery or electrical SOC can be vehicle. influenced This bypaper the analyzes and compares the strengths and weaknesses of typical estimation methods which have been studied by research- ers. By comparing these advantages and disadvantages of various methods, this paper presents proper estimation methods suitable for energy storage applications. Keywords: Ampere Hour Counting, Electrochemical Impedance Spectroscopy, Open Circuit Voltage, Kalman Filter, SOC (State of Charge) 1. Introduction 2. State-of-Charge Estimation According to the depletion of -
SI and CGS Units in Electromagnetism
SI and CGS Units in Electromagnetism Jim Napolitano January 7, 2010 These notes are meant to accompany the course Electromagnetic Theory for the Spring 2010 term at RPI. The course will use CGS units, as does our textbook Classical Electro- dynamics, 2nd Ed. by Hans Ohanian. Up to this point, however, most students have used the International System of Units (SI, also known as MKSA) for mechanics, electricity and magnetism. (I believe it is easy to argue that CGS is more appropriate for teaching elec- tromagnetism to physics students.) These notes are meant to smooth the transition, and to augment the discussion in Appendix 2 of your textbook. The base units1 for mechanics in SI are the meter, kilogram, and second (i.e. \MKS") whereas in CGS they are the centimeter, gram, and second. Conversion between these base units and all the derived units are quite simply given by an appropriate power of 10. For electromagnetism, SI adds a new base unit, the Ampere (\A"). This leads to a world of complications when converting between SI and CGS. Many of these complications are philosophical, but this note does not discuss such issues. For a good, if a bit flippant, on- line discussion see http://info.ee.surrey.ac.uk/Workshop/advice/coils/unit systems/; for a more scholarly article, see \On Electric and Magnetic Units and Dimensions", by R. T. Birge, The American Physics Teacher, 2(1934)41. Electromagnetism: A Preview Electricity and magnetism are not separate phenomena. They are different manifestations of the same phenomenon, called electromagnetism. One requires the application of special relativity to see how electricity and magnetism are united. -
The ST System of Units Leading the Way to Unification
The ST system of units Leading the way to unification © Xavier Borg B.Eng.(Hons.) - Blaze Labs Research First electronic edition published as part of the Unified Theory Foundations (Feb 2005) [1] Abstract This paper shows that all measurable quantities in physics can be represented as nothing more than a number of spatial dimensions differentiated by a number of temporal dimensions and vice versa. To convert between the numerical values given by the space-time system of units and the conventional SI system, one simply multiplies the results by specific dimensionless constants. Once the ST system of units presented here is applied to any set of physics parameters, one is then able to derive all laws and equations without reference to the original theory which presented said relationship. In other words, all known principles and numerical constants which took hundreds of years to be discovered, like Ohm's Law, energy mass equivalence, Newton's Laws, etc.. would simply follow naturally from the spatial and temporal dimensions themselves, and can be derived without any reference to standard theoretical background. Hundreds of new equations can be derived using the ST table included in this paper. The relation between any combination of physical parameters, can be derived at any instant. Included is a step by step worked example showing how to derive any free space constant and quantum constant. 1 Dimensions and dimensional analysis One of the most powerful mathematical tools in science is dimensional analysis. Dimensional analysis is often applied in different scientific fields to simplify a problem by reducing the number of variables to the smallest number of "essential" parameters. -
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. -
CAR-ANS Part 5 Governing Units of Measurement to Be Used in Air and Ground Operations
CIVIL AVIATION REGULATIONS AIR NAVIGATION SERVICES Part 5 Governing UNITS OF MEASUREMENT TO BE USED IN AIR AND GROUND OPERATIONS CIVIL AVIATION AUTHORITY OF THE PHILIPPINES Old MIA Road, Pasay City1301 Metro Manila UNCOTROLLED COPY INTENTIONALLY LEFT BLANK UNCOTROLLED COPY CAR-ANS PART 5 Republic of the Philippines CIVIL AVIATION REGULATIONS AIR NAVIGATION SERVICES (CAR-ANS) Part 5 UNITS OF MEASUREMENTS TO BE USED IN AIR AND GROUND OPERATIONS 22 APRIL 2016 EFFECTIVITY Part 5 of the Civil Aviation Regulations-Air Navigation Services are issued under the authority of Republic Act 9497 and shall take effect upon approval of the Board of Directors of the CAAP. APPROVED BY: LT GEN WILLIAM K HOTCHKISS III AFP (RET) DATE Director General Civil Aviation Authority of the Philippines Issue 2 15-i 16 May 2016 UNCOTROLLED COPY CAR-ANS PART 5 FOREWORD This Civil Aviation Regulations-Air Navigation Services (CAR-ANS) Part 5 was formulated and issued by the Civil Aviation Authority of the Philippines (CAAP), prescribing the standards and recommended practices for units of measurements to be used in air and ground operations within the territory of the Republic of the Philippines. This Civil Aviation Regulations-Air Navigation Services (CAR-ANS) Part 5 was developed based on the Standards and Recommended Practices prescribed by the International Civil Aviation Organization (ICAO) as contained in Annex 5 which was first adopted by the council on 16 April 1948 pursuant to the provisions of Article 37 of the Convention of International Civil Aviation (Chicago 1944), and consequently became applicable on 1 January 1949. The provisions contained herein are issued by authority of the Director General of the Civil Aviation Authority of the Philippines and will be complied with by all concerned.