## Metric and British Units |

One of the principal advantages of the Metric System is its use of only one unit (standard of size) for each parameter (thing that is being measured). The metric units are interrelated in such a way that only five fundamental standards are necessary. These fundamental standards are identified with an * in the tables below.

Parameter: | Metric Unit | British Units |
---|---|---|

timeduration, delay | second *s | second, minute
hour, day |

frequency | hertz1/s | cycle per second |

lengthdistance, displacement | meter1/299 792 458 light sec m | inch, foot, yard
rod, chain, furlong, mile |

velocity, speedrate of change of position | meter per second
m/s | foot per second mile per hour, knot |

accelerationrate of change of velocity | meter per second squared
m/s ^{2} | foot per second squared |

massquantity of material | kilogram *kg | ounce, pound, slug, ton |

forcepush, pull, or weight | newtonkg m/s ^{2}
| pound-force |

impulseforce times time | newton secondkg m/s | pound-force second |

momentummass times velocity | kilogram meter per second
kg m/s | pound foot per second |

work, energyforce times distance | joule (pronounced "jewel")
= one newton meter kg m ^{2}/s^{2} | foot pound-force |

powerrate of doing work | watt= one joule per second kg m ^{2}/s^{3} | foot pound-force per second horsepower |

areasize of a surface | square meter
m ^{2} | square foot, square yard
acre, square mile |

pressureforce per unit area | pascalnewton per square meter kg/m s ^{2} | pound-force per square inch |

volume, capacity | cubic meter (stere)m ^{3} | pint, quart, gallon cubic foot, cubic yard |

density, heaviness | grams per cubic centimeter
g/cm ^{3} | pounds per cubic foot |

Parameter: | Metric Heat Unit | British Heat Unit |
---|---|---|

heat energy | joule, jcalorie, Calorie 1 cal = 4.186 joules 1 Cal = 4186 joules |
British Thermal Unit, BTU |

temperature change | kelvins, K * |
Fahrenheit degree, Fº |

temperature | kelvins, K |
degrees Fahrenheit, ºF |

Parameter: | Metric Light Unit |
---|---|

luminous intensity | candle * |

luminous flux | lumen one candle produces 4 pi lumens |

illumination | luxlumen per square meter |

focus | diopterreciprocal meters |

astronomical distance | parsec |

Parameter: | Metric Electrical Unit |
---|---|

electric charge | coulomb *96,500 coul = 1 faraday faraday = 1 mole of electrons |

electromotive force (EMF) | volt (joule per coulomb) |

capacitance | farad (coulomb per volt) |

electric current | ampere (coulomb per second) |

electric energy | joule (watt second)(newton meter) KWH = 3,600,000 joules |

electric power | watt (joule per second) |

electrical resistance | ohm(volt per ampere) |

electrical conductivity | siemens (coulomb per joule)(ampere per volt) |

electrical field strength | volts per meter |

electromagnetic inductance | henry (pl. henrys) |

magnetic field intensity | oersted (formerly the gauss) |

magnetic flux | weber (10^{8} maxwells) |

magnetic flux density | teslaweber per square meter |

magnetomotive force | gilbert |