by Nikolai V. Shokhirev

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Walker group units of measures

Introduction

SI units

Basic interactions

Dimensions and units

Numeric values of the fundamental constants

Energy Units

Magnetic resonance in SI units

 

Introduction

This page was originally developed as reference data for Dr. Walker Research Group.

The large variety of the units of measures used in different areas and in different times causes a great deal of confusion. Obviously any particular set of units can be recalculated to another. This can be done if we have well-defined standard units and reliable conversion factors. Below we use the SI system of units as a standard. Note that the SI units are not necessarily the most convenient in some specific areas.

SI units

For basic definition and details visit the site A Dictionary of Units of Measurement by Russ Rowlett: http://www.unc.edu/~rowlett/units/index.html  and National Institute of Standards and Technology http://physics.nist.gov/ 

 Base quantity  Symbol   Name  Unit
 
 Basic units      
 Length  L  meter  m
 Mass  M  kilogram  kg
 Time  T  second  s
 Electric current  I  ampere  A
 Thermodynamic temperature  K  kelvin  K
 Amount of substance    mole  mol
 Luminous intensity    candela  cd
 
 Derived units      
 Frequency    hertz  Hz = s -1
 Force  F  newton  N = m·kg·s -2
 energy, work, quantity of heat  E  joule  J = N·m = m 2·kg·s -2
 Power    watt  W = J/s = m 2·kg·s -3
 Pressure  P  pascal  Pa = N/m 2 = m -1·kg·s -2
       
 Electric charge, quantity of electricity  Q  coulomb A s
 Electric potential difference, electromotive force   V  volt V = W/A
= m 2·kg·s -3·A -1
 Capacitance  C  farad F = C / V = m -2·kg -1·s 4·A 2
 Electric resistance    ohm  = V / A = m 2·kg·s -3·A -2
 Electric conductance
 siemens S = A/V = m -2·kg -1·s 3·A 2
       
 magnetic flux    weber Wb = V·s = m 2·kg·s -2·A -1
 magnetic flux density B  tesla T = Wb/m 2 = kg·s -2·A -1
 Inductance    henry H = Wb/A = m 2·kg·s -2·A -2

The basic physical interactions are presented in the next section.

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