Introduction to Mechanical Engineering Measurements Author: John M
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5 Military Rucking Rules Every Backpacker Should Know 1. One
5 Military Rucking Rules Every Backpacker Should Know The military has spent years studying the best way to move under a load (aka “rucking”). Here are 5 military rucking rules that translate well to hikers. “Rucking” is the military term for hiking under load. As you can imagine, this is a huge issue for the military, as soldiers must wear body armor and carry weapons, ammo, water, communications equipment, and other gear as they conduct patrols and missions. Rucking performance and injury prevention are hugely important for military operations and personnel. Movement over ground under load is also a key for hiking and backpacking. In reviewing the research the military has already done on this subject, we discovered five rules. Read on to make sure you’re following these military rucking rules on your next backcountry adventure. 1. One pound on your feet equals five pounds on your back. This old backpacking thumb rule holds true, according to a 1984 study from the U.S. Army Research Institute. They tested how much more energy was expended with different footwear (boots and shoes) and concluded that it take 4.7 to 6.4 times as much energy to move at a given pace when weight is carried on the shoe versus on the torso. In practical terms, this means you could carry half a gallon more of water (a little over 4 pounds) if you buy boots that are a pound lighter, which isn’t hard to do; and that’s a lot of water. Now imagine the energy savings of backpacking in light trail running shoes rather than heavy, leather backpacking boots over the course of 7- day backpacking trip. -
Conversion Factor Table Copyright © by Jon Wittwer
Conversion Factor Table http://www.et.byu.edu/~jww8 Copyright © by Jon Wittwer Multiple by To Get hp 2544.5 Btu / hr m / s 3.60 km / h inch 2.54 cm hp 745.70 W (watt) m / s 3.2808 ft / s This can also be written as: 1 inch = 2.54 cm hp 0.74570 kW m / s 2.237 mi / h (mph) A acre 43,560 ft2 hp 33,000 ft·lbf / min m / s2 3.2808 ft / s2 ampere·hr (A·h) 3,600 coulomb (C) hp 550 ft·lbf / sec metric ton 1000 kg hp·hr 2544 Btu ångström (Å) 1x10-10 m mil 0.001 in 6 atm (atmosphere) 1.01325 bar hp·hr 1.98x10 ft·lbf mi (mile) 5280 ft atm, std 76.0 cm of Hg hp·hr 2.68x106 J mi 1.6093 km atm, std 760 mm of Hg at 0ºC in 2.54* cm mi2 (square mile) 640 acres atm, std 33.90 ft of water in of Hg 0.0334 atm mph (mile/hour) 1.6093 km / hr atm, std 29.92 in of Hg at 30ºF in of Hg 13.60 in of water mph 88.0 ft / min (fpm) atm, std 14.696 lbf/in2 abs (psia) in of Hg 3.387 kPa mph 1.467 ft / s atm, std 101.325 kPa in of water 0.0736 in of Hg mph 0.4470 m / s 2 -6 atm, std 1.013x105 Pa in of water 0.0361 lbf / in (psi) micron 1x10 m in of water 0.002458 atm -3 atm, std 1.03323 kgf / cm2 mm of Hg 1.316x10 atm -4 atm, std 14.696 psia J J (joule) 9.4782x10 Btu mm of Hg 0.1333 kPa B bar 0.9869 atm, std J 6.2415x1018 eV mm of water 9.678x10-5 atm bar 1x105 Pa J 0.73756 ft·lbf N N (newton) 1 kg·m / s2 J1N·m Btu 778.169 ft·lbf N 1x105 dyne 7 Btu 1055.056 J J 1x10 ergs µN (microN) 0.1 dyne Btu 5.40395 psia·ft3 J / s 1 W N 0.22481 lbf K kg (kilogram) 2.2046226 lbm (pound mass) Btu 2.928x10-4 kWh N·m 0.7376 ft·lbf -5 kg 0.068522 slug N·m 1 J Btu 1x10 therm -3 kg 1x10 metric -
Weights and Measures Standards of the United States: a Brief History
1 .0 11 8 1.25 1.4 I 6_ DOCUMENT RESUME ED 142 418 SE 022 719 AUTHOE Judson, Lewis V. TITLE Weights and Measures Standards of the United States: A Brief History. Updated Edition. INSTITUTION National Bureau of Standards (DOC) ,Washington, D.C. REPORT NO NBS-SP-447 PUB DATE Mar 76 NOTE 42p.; Contains occasional small print; Photographs may not reproduce well AVAILABLE FROM Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402 (Stock Number 003-0O3-01654-3, $1.00) EDRS PRICE MF-$0.83 HC-$2.06 Plus Postage. DESCRIPTORS Government Publications; History; *Mathematics Education; *Measurement; *Metric System; *Science History; *Standards ABSTRACT This document was published by the National Bureau of Standards to meet the current demand for information on the history of weights and measures in the United States. It includes an illustrated discussion of this history through 1962 followed by an addendum covering the period 1963-1975. Appendices provide a bibliography and photographic copies of eight documents important to the development of official standards of measurement. (SD) *********************************************************************** Documents acquired by ERIC include many informal unpublished * materials not available from other sources. ERIC makes every effort * * -to obtain the best copy available. Nevertheless, items of marginal * * reproducibility are often encountered and this affects the quality * * of the microfiche and hardcopy reproductions ERIC makes available * via the ERIC Document Reproduction Service (EDRS). EDRS is not * responsible for the quality of the original document. Reproductions * * supplied by EDRS are the best that can be made from the original. *********************************************************************** U.S. DEPARTMENT OF HEALTH. -
Multidisciplinary Design Project Engineering Dictionary Version 0.0.2
Multidisciplinary Design Project Engineering Dictionary Version 0.0.2 February 15, 2006 . DRAFT Cambridge-MIT Institute Multidisciplinary Design Project This Dictionary/Glossary of Engineering terms has been compiled to compliment the work developed as part of the Multi-disciplinary Design Project (MDP), which is a programme to develop teaching material and kits to aid the running of mechtronics projects in Universities and Schools. The project is being carried out with support from the Cambridge-MIT Institute undergraduate teaching programe. For more information about the project please visit the MDP website at http://www-mdp.eng.cam.ac.uk or contact Dr. Peter Long Prof. Alex Slocum Cambridge University Engineering Department Massachusetts Institute of Technology Trumpington Street, 77 Massachusetts Ave. Cambridge. Cambridge MA 02139-4307 CB2 1PZ. USA e-mail: [email protected] e-mail: [email protected] tel: +44 (0) 1223 332779 tel: +1 617 253 0012 For information about the CMI initiative please see Cambridge-MIT Institute website :- http://www.cambridge-mit.org CMI CMI, University of Cambridge Massachusetts Institute of Technology 10 Miller’s Yard, 77 Massachusetts Ave. Mill Lane, Cambridge MA 02139-4307 Cambridge. CB2 1RQ. USA tel: +44 (0) 1223 327207 tel. +1 617 253 7732 fax: +44 (0) 1223 765891 fax. +1 617 258 8539 . DRAFT 2 CMI-MDP Programme 1 Introduction This dictionary/glossary has not been developed as a definative work but as a useful reference book for engi- neering students to search when looking for the meaning of a word/phrase. It has been compiled from a number of existing glossaries together with a number of local additions. -
U.S. Metric Study Interim Report
U.S. METRIC STUDY INTERIM REPORT THE CONSUMER imHHMHPHr U.S. METRIC SUBSTUDY REPORTS The results of substudies of the U.S. Metric Study, while being evaluated for the preparation of a comprehensive report to the Congress, are being published in the interim as a series of NBS Special Publications. The titles of the individual reports are listed below. REPORTS ON SUBSTUDIES NBS SP345-I: International Standards (issued December 1970, SD Catalog No. CI 3. 10:345-1, Price $1.25) NBS SP345-2: Federal Government: Civilian Agencies (issued July 1971, SD Catalog No. CI 3. 10:345-2, price $2.25) NBS SP345-3: Commercial Weights and Measures (issued July 1971, SD Catalog No. CI 3. 10:345-3, price $1.00) NBS SP345-4: The Manufacturing Industry (issued July 1971, SD Catalog No. C 1 3. 10:345-4, price $ 1 .25) NBS SP345-5 Nonmanufacturing Businesses (in press) NBS SP345-6 Education (in press) NBS SP345-7 The Consumer (this publication) NBS SP345-8 International Trade (in press) NBS SP345-9 Department of Defense (issued July 1971, SD Catalog No. C 1 3. 1 0:345-9, price $ 1 .25) NBS SP345-10: A History of the Metric System Controversy in the United States (in press) NBSSP345-11: Engineering Standards (issued July 1971, SD Catalog No. C 1 3. 1 0:345-1 1 , price $2.00) NBSSP345-12: Testimony of Nationally Representative Groups (issued July 1971, SD Catalog No. C13. 10:345-12, price $1.50) COMPREHENSIVE REPORT ON THE U.S. METRIC STUDY NBS SP345: To be published in August 1971 Those publications with catalog numbers have already been issued, and may be purchased from the Superintendent of Documents, Government Printing Office, Washington, D.C. -
Fundamentals of Math CHAPTER 1
© Jones and Bartlett Publishers, LLC. NOT FOR SALE OR DISTRIBUTION Fundamentals of Math CHAPTER 1 OBJECTIVES ■ Understand the difference between the Arabic and Roman numeral systems ■ Translate Arabic numerals to Roman numerals ■ Translate Roman numerals to Arabic numerals ■ Understand the metric system ■ Understand the apothecary system ■ Be able to convert metric to apothecary ■ Be able to convert apothecary to metric ARABIC NUMERALS The Arabic number system uses the numerals 1, 2, 3, 4, 5, 6, 7, 8, 9, and zero (0). It is also known as the decimal system. Depending on how these numbers are arranged determines the value of the number. For example, digits 4, 7, and 2 placed together (472) represent the number four hundred seventy-two. A decimal point (.) separates whole numbers, or units, from fractional num- bers, or fractional units. All numbers on the left side of the decimal point are considered whole numbers. All numbers placed on the right of the decimal point are considered fractional units, or less than one whole unit. The following num- ber line shows the relationship of Arabic numerals based on their position in a number. Ten-thousands hundreds ones tenths thousandths hundred-thousandths -----5------8------2-----4-----3---- . ----6------7------9------3------2-------------- thousands tens hundredths ten-thousandths The number 43.6 contains the numerals 4, 3, and 6. This represents forty-three units of one and six-tenths of one unit. Decimals will be covered in more detail in Chapter 2. 1 59612_CH01_FINAL.indd 1 8/20/09 7:38:45 PM © Jones and Bartlett Publishers, LLC. NOT FOR SALE OR DISTRIBUTION 2 Chapter 1 ■ Fundamentals of Math ROMAN NUMERALS The Roman numeral system does not utilize numerals. -
Student Academic Learning Services Pounds Mass and Pounds Force
Student Academic Learning Services Page 1 of 3 Pounds Mass and Pounds Force One of the greatest sources of confusion in the Imperial (or U.S. Customary) system of measurement is that both mass and force are measured using the same unit, the pound. The differentiate between the two, we call one type of pound the pound-mass (lbm) and the other the pound-force (lbf). Distinguishing between the two, and knowing how to use them in calculations is very important in using and understanding the Imperial system. Definition of Mass The concept of mass is a little difficult to pin down, but basically you can think of the mass of an object as the amount of matter contain within it. In the S.I., mass is measured in kilograms. The kilogram is a fundamental unit of measure that does not come from any other unit of measure.1 Definition of the Pound-mass The pound mass (abbreviated as lbm or just lb) is also a fundamental unit within the Imperial system. It is equal to exactly 0.45359237 kilograms by definition. 1 lbm 0.45359237 kg Definition of Force≡ Force is an action exerted upon an object that causes it to accelerate. In the S.I., force is measured using Newtons. A Newton is defined as the force required to accelerate a 1 kg object at a rate of 1 m/s2. 1 N 1 kg m/s2 Definition of ≡the Pound∙ -force The pound-force (lbf) is defined a bit differently than the Newton. One pound-force is defined as the force required to accelerate an object with a mass of 1 pound-mass at a rate of 32.174 ft/s2. -
U5 Determining Density
Presentation Name Course Name Unit # – Lesson #.# – Lesson Name Density • Density is a measure of the amount of matter per unit of volume Determining Density High Density Low Density – Objects more dense than water sink – Objects less dense than water float Matter: Mass vs. Weight Matter: Mass vs. Weight Mass and Weight are often confused • Mass is the amount of matter in an object or the • An example using SI units quantity of the inertia of the object – A man has a mass of 100 kg • Weight is the force of gravity on mass W = mg W = mg 2 W = (100 kg)(9.8 m/sec ) W = weight = 980 Newton m = mass g = acceleration of gravity – He weighs 980 N • Many materials are purchased by weight Project Lead The Way, Inc. Copyright 2010 1 Presentation Name Course Name Unit # – Lesson #.# – Lesson Name Matter: Mass vs. Weight Mass vs. Weight Mass and Weight are often confused • Pound-mass (lbm) is a unit of mass • US Customary units example . 1 lbm = 0.45359237 kg (by definition) – A woman weighs 100 pounds . 1 kg = 2.205 lbm (formula sheet) . 1 slug = 32.2 lbm (formula sheet) W = mg W Formula Sheet m = g 100 lb = = 3.1 slugs ft 32.2 s2 – Her mass is 3.1 slugs Mass vs. Weight Mass vs. Weight • Pound-force (lb) is a unit of force • How are pound-mass and pound-force . The gravitational force exerted on a mass of related? 2 one lbm on the surface of the Earth – On Earth (g = 32.174 ft/s ) . -
Grades, Standards
Grades, Standards 'Tîi.i^' In S,ny exchange of goods the buyer and seller must agree on how much of a com- modity is to be delivered. As soon as trade gets beyond simple barter, it has to depend therefore on weights and measures. Likewise, all trading, except simple barter, in- volves price. Price in practically all markets is a com- mon denominator by which are expressed unlike details of size, amount, weight, and quality of products being traded. Besides weights and measures, therefore, stand- ards for other attributes of goods have been developed. Grading is a basic function in practically all transactions. 142 The purpose is to establish a common language under- stood by buyers and sellers as a basis of judging the quality of a product in relation to its sales price. Grades are useful to all persons who engage in trade. They are also useful in describing the quality of many consumers' retail goods. Controversy over compulsory grade label- ing of consumer goods has waxed strong, however. Much of the argument has been concerned with the system of grading to use. systems of units the old names often Units and remain in-use. In Paris, after loo years of compulsory use of the metric system, hucksters still cry the price of fruit per Standards of livre (pound), just as the Berliner talks of the Pfund, even though the weight of each is actually a half kilogram. Measurement Our own customs are equally hard to change even when they cause some real trouble: We still give statistics on In any exchange of goods the seller grains in bushels, although by law and buyer must agree on how much deliveries must be by w^eight and al- of a commodity is to be delivered. -
Weights and Measures Standards of the United States—A Brief History (1963), by Lewis V
WEIGHTS and MEASURES STANDARDS OF THE UMIT a brief history U.S. DEPARTMENT OF COMMERCE NATIONAL BUREAU OF STANDARDS NBS Special Publication 447 WEIGHTS and MEASURES STANDARDS OF THE TP ii 2ri\ ii iEa <2 ^r/V C II llinCAM NBS Special Publication 447 Originally Issued October 1963 Updated March 1976 For sale by the Superintendent of Documents, U.S. Government Printing Office Wash., D.C. 20402. Price $1; (Add 25 percent additional for other than U.S. mailing). Stock No. 003-003-01654-3 Library of Congress Catalog Card Number: 76-600055 Foreword "Weights and Measures," said John Quincy Adams in 1821, "may be ranked among the necessaries of life to every individual of human society." That sentiment, so appropriate to the agrarian past, is even more appropriate to the technology and commerce of today. The order that we enjoy, the confidence we place in weighing and measuring, is in large part due to the measure- ment standards that have been established. This publication, a reprinting and updating of an earlier publication, provides detailed information on the origin of our standards for mass and length. Ernest Ambler Acting Director iii Preface to 1976 Edition Two publications of the National Bureau of Standards, now out of print, that deal with weights and measures have had widespread use and are still in demand. The publications are NBS Circular 593, The Federal Basis for Weights and Measures (1958), by Ralph W. Smith, and NBS Miscellaneous Publication 247, Weights and Measures Standards of the United States—a Brief History (1963), by Lewis V. -
Imperial Units
Imperial units From Wikipedia, the free encyclopedia Jump to: navigation, search This article is about the post-1824 measures used in the British Empire and countries in the British sphere of influence. For the units used in England before 1824, see English units. For the system of weight, see Avoirdupois. For United States customary units, see Customary units . Imperial units or the imperial system is a system of units, first defined in the British Weights and Measures Act of 1824, later refined (until 1959) and reduced. The system came into official use across the British Empire. By the late 20th century most nations of the former empire had officially adopted the metric system as their main system of measurement. The former Weights and Measures office in Seven Sisters, London. Contents [hide] • 1 Relation to other systems • 2 Units ○ 2.1 Length ○ 2.2 Area ○ 2.3 Volume 2.3.1 British apothecaries ' volume measures ○ 2.4 Mass • 3 Current use of imperial units ○ 3.1 United Kingdom ○ 3.2 Canada ○ 3.3 Australia ○ 3.4 Republic of Ireland ○ 3.5 Other countries • 4 See also • 5 References • 6 External links [edit] Relation to other systems The imperial system is one of many systems of English or foot-pound-second units, so named because of the base units of length, mass and time. Although most of the units are defined in more than one system, some subsidiary units were used to a much greater extent, or for different purposes, in one area rather than the other. The distinctions between these systems are often not drawn precisely. -
Fluid Mechanics
I. FLUID MECHANICS I.1 Basic Concepts & Definitions: Fluid Mechanics - Study of fluids at rest, in motion, and the effects of fluids on boundaries. Note: This definition outlines the key topics in the study of fluids: (1) fluid statics (fluids at rest), (2) momentum and energy analyses (fluids in motion), and (3) viscous effects and all sections considering pressure forces (effects of fluids on boundaries). Fluid - A substance which moves and deforms continuously as a result of an applied shear stress. The definition also clearly shows that viscous effects are not considered in the study of fluid statics. Two important properties in the study of fluid mechanics are: Pressure and Velocity These are defined as follows: Pressure - The normal stress on any plane through a fluid element at rest. Key Point: The direction of pressure forces will always be perpendicular to the surface of interest. Velocity - The rate of change of position at a point in a flow field. It is used not only to specify flow field characteristics but also to specify flow rate, momentum, and viscous effects for a fluid in motion. I-1 I.4 Dimensions and Units This text will use both the International System of Units (S.I.) and British Gravitational System (B.G.). A key feature of both is that neither system uses gc. Rather, in both systems the combination of units for mass * acceleration yields the unit of force, i.e. Newton’s second law yields 2 2 S.I. - 1 Newton (N) = 1 kg m/s B.G. - 1 lbf = 1 slug ft/s This will be particularly useful in the following: Concept Expression Units momentum m! V kg/s * m/s = kg m/s2 = N slug/s * ft/s = slug ft/s2 = lbf manometry ρ g h kg/m3*m/s2*m = (kg m/s2)/ m2 =N/m2 slug/ft3*ft/s2*ft = (slug ft/s2)/ft2 = lbf/ft2 dynamic viscosity µ N s /m2 = (kg m/s2) s /m2 = kg/m s lbf s /ft2 = (slug ft/s2) s /ft2 = slug/ft s Key Point: In the B.G.