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== | {{Redirect|Unit of measure}} | ||
{{Redirect|Weights and measures}} | |||
[[Image:Weights and Measures office.jpg|thumb|upright=1.5|right|The former Weights and Measures office in [[Seven Sisters, London]]]] | |||
[[File:Unità di misura - Palazzo della Ragione - Padova.jpg|thumb|upright=1.5|right|Units of measurement, [[Palazzo della Ragione]], [[Padua]]]] | |||
A '''unit of measurement''' is a definite [[magnitude (mathematics)|magnitude]] of a [[physical quantity]], defined and adopted by convention or by law, that is used as a standard for measurement of the same physical quantity.<ref>{{VIM3rd|term=measurement unit|pages=6–7}}.</ref> Any other value of the physical quantity can be expressed as a simple multiple of the unit of measurement. | |||
For example, [[length]] is a physical quantity. The [[metre]] is a unit of length that represents a definite predetermined length. When we say 10 metres (or 10 m), we actually mean 10 times the definite predetermined length called "metre". | |||
The definition, agreement, and practical use of units of measurement have played a crucial role in human endeavour from early ages up to this day. Different [[System of measurement|systems of units]] used to be very common. Now there is a global standard, the [[International System of Units]] (SI), the modern form of the [[metric system]]. | |||
In trade, '''weights and measures''' is often a subject of governmental regulation, to ensure fairness and transparency. The [[International Bureau of Weights and Measures]] (BIPM) is tasked with ensuring worldwide uniformity of measurements and their traceability to the International System of Units (SI). [[Metrology]] is the science for developing nationally and internationally accepted units of weights and measures. | |||
In [[physics]] and [[metrology]], units are standards for [[measurement]] of [[physical quantity|physical quantities]] that need clear definitions to be useful. [[Reproducibility]] of experimental results is central to the [[scientific method]]. A standard system of units facilitates this. Scientific systems of units are a refinement of the concept of weights and measures developed long ago for commercial purposes. | |||
[[Science]], [[medicine]], and [[engineering]] often use larger and smaller units of measurement than those used in everyday life and indicate them more precisely. The judicious selection of the units of measurement can aid researchers in [[problem solving]] (see, for example, [[dimensional analysis]]). | |||
In the [[social sciences]], there are no standard units of measurement and the theory and practice of measurement is studied in [[psychometrics]] and the [[theory of conjoint measurement]]. | |||
==History== | |||
{{main|History of measurement}} | |||
A unit of measurement is a standardised [[quantity]] of a physical property, used as a factor to express occurring quantities of that property. Units of measurement were among the earliest tools invented by humans. Primitive societies needed rudimentary measures for many tasks: constructing dwellings of an appropriate size and shape, fashioning clothing, or bartering food or raw materials. | |||
The earliest known uniform systems of weights and measures seem to have all been created sometime in the [[4th millennium BC|4th]] and [[3rd millennium BC|3rd millennia BC]] among the ancient peoples of [[Mesopotamia]], [[Ancient Egypt|Egypt]] and the [[Indus Valley Civilization|Indus Valley]], and perhaps also [[Elam]] in [[Iran|Persia]] as well. | |||
Weights and measures are mentioned in the Bible (Leviticus 19:35-36). It is a commandment to be honest and have fair measures. | |||
In "The [[Magna Carta]]" of 1215 (The Great Charter) with the seal of [[John, King of England|King John]], put before him by the Barons of England, King John agreed in Clause 35 "There shall be one measure of wine throughout our whole realm, and one measure of ale and one measure of corn--namely, the London quart;--and one width of dyed and russet and hauberk cloths--namely, two ells below the selvage..."<ref>[http://www.frauncestavernmuseum.org/magna_carta/MCFF-Education-Packet.pdf ]{{dead link|date=June 2012}}</ref> | |||
Many systems were based on the use of parts of the body and the natural surroundings as measuring instruments. Our present knowledge of early weights and measures comes from many sources. | |||
==Systems of units== | |||
{{main|System of measurement}} | |||
===Traditional systems=== | |||
Historically many of the systems of measurement which had been in use were to some extent based on the dimensions of the human body according to the proportions described by [[Marcus Vitruvius Pollio]].{{citation needed|date=December 2011}} As a result, units of measure could vary not only from location to location, but from person to person. | |||
===Metric systems=== | |||
A number of [[metric system]]s of units have [[History of the metric system|evolved since the adoption of the original metric system]] in [[France]] in 1791. The current international standard metric system is the [[SI|International System of Units]]. An important feature of modern systems is [[standardization]]. Each unit has a universally recognized size. | |||
Both the [[Imperial unit]]s and [[US customary units]] derive from earlier [[English unit]]s. Imperial units were mostly used in the [[Commonwealth of Nations|British Commonwealth]] and the former [[British Empire]]. US customary units are still the main system of measurement used in the [[United States]] despite Congress having legally authorized metric measure on 28 July 1866.<ref> | |||
{{cite web | |||
|url=http://lamar.colostate.edu/~hillger/laws/metric-act.html | |||
|title=US Metric Act of 1866 | |||
}} as amended by Public Law 110–69 dated August 9, 2007</ref> Some steps towards US [[metrication]] have been made, particularly the redefinition of basic US and imperial units to derive exactly from SI units. Since the [[international yard and pound]] agreement of 1959 the US and imperial inch is now defined as exactly 0.0254 m, and the US and imperial avoirdupois pound is now defined as exactly 453.59237 g.<ref> | |||
{{cite web | |||
|url=http://ts.nist.gov/WeightsAndMeasures/h44-04.cfm | |||
|title=NIST Handbook 44 Appendix B | |||
|year=2002 | |||
|publisher=[[National Institute of Standards and Technology]] | |||
}}</ref> | |||
===Natural systems=== | |||
While the above systems of units are based on arbitrary unit values, formalised as standards, some unit values occur naturally in science. Systems of units based on these are called [[natural units]]. Similar to natural units, [[atomic units]] (au) are a convenient [[system of units]] of measurement used in [[atomic physics]]. | |||
Also a great number of [[List of unusual units of measurement|unusual]] and non-standard units may be encountered. These may include the [[Solar mass]] (2 x 10<sup>30</sup> kg) and the [[TNT equivalent|Megaton]] (1,000,000 tons of [[Trinitrotoluene|TNT]]). | |||
===Legal control of weights and measures=== | |||
{{Main|Weights and Measures Act|Trading standards}} | |||
To reduce the incidence of retail fraud, many national [[statutes]] have standard definitions of weights and measures that may be used (hence "statute measure"), and these are verified by legal officers. | |||
==Base and derived units==<!-- This section is linked from [[Measurement]] --> | |||
Different systems of units are based on different choices of a set of [[fundamental unit]]s. | |||
The most widely used system of units is the International System of Units, or [[SI]]. There are seven [[SI base unit]]s. All [[SI derived unit|other SI units]] can be derived from these base units. | |||
For most quantities a unit is absolutely necessary to communicate values of that physical quantity. For example, conveying to someone a particular length without using some sort of unit is impossible, because a length cannot be described without a reference used to make sense of the value given. | |||
But not all quantities require a unit of their own. Using physical laws, units of quantities can be expressed as combinations of units of other quantities. Thus only a small set of units is required. These units are taken as the ''base units''. Other units are ''derived units''. Derived units are a matter of convenience, as they can be expressed in terms of basic units. Which units are considered base units is a matter of choice. | |||
The base units of SI are actually not the smallest set possible. Smaller sets have been defined. For example, there are unit sets{{Which|date=February 2011}} in which the [[electric field|electric]] and [[magnetic field]] have the same unit. This is based on physical laws that show that electric and magnetic field are actually different manifestations of the same phenomenon. | |||
==Calculations with units of measurements== | |||
{{howto|section|date=December 2011}} | |||
{{merge-from|Units conversion by factor-label|date=June 2013|section=yes}} | |||
{{merge-from|Conversion factor|date=June 2013|section=yes}} | |||
===Units as dimensions=== | |||
Any value of a [[physical quantity]] is expressed as a comparison to a unit of that quantity. For example, the value of a physical quantity ''Z'' is expressed as the product of a unit [Z] and a numerical factor: | |||
:<math>Z = n \times [Z] = n [Z].</math> For example, "2 candlesticks" Z = 2 [candlestick]. | |||
The multiplication sign is usually left out, just as it is left out between variables in scientific notation of formulas. The conventions used to express quantities is referred to as [[quantity calculus]]. In formulas the unit [Z] can be treated as if it were a specific magnitude of a kind of physical [[dimension]]: see [[dimensional analysis]] for more on this treatment. | |||
Units can only be added or subtracted if they are the same type; however units can always be multiplied or divided, as [[George Gamow]] used to explain: | |||
:"2 candlesticks" times "3 cabdrivers" = 6 [candlestick][cabdriver]. | |||
A distinction should be made between units and standards. A unit is fixed by its definition, and is independent of physical conditions such as temperature. By contrast, a standard is a physical realization of a unit, and realizes that unit only under certain physical conditions. For example, the metre is a unit, while a metal bar is a standard. One metre is the same length regardless of temperature, but a metal bar will be exactly one metre long only at a certain temperature. | |||
===Guidelines=== | |||
* Treat units algebraically. Only add like terms. When a unit is divided by itself, the division yields a unitless one. When two different units are multiplied, the result is a new unit, referred to by the combination of the units. For instance, in SI, the unit of speed is metres per second (m/s). See [[dimensional analysis]]. A unit can be multiplied by itself, creating a unit with an exponent (e.g. m<sup>2</sup>/s<sup>2</sup>). Put simply, units obey the laws of indices. (See [[Exponentiation]].) | |||
* Some units have special names, however these should be treated like their equivalents. For example, one newton (N) is equivalent to one kg·m/s<sup>2</sup>. Thus a quantity may have several unit designations, for example: the unit for [[surface tension]] can be referred to as either N/m (newtons per metre) or kg/s<sup>2</sup> (kilograms per second squared). Whether these designations are equivalent is disputed amongst metrologists.<ref name="Emerson">{{Cite journal | title = On quantity calculus and units of measurement | first = W.H. | last = Emerson | year = 2008 |journal = [[Metrologia]] | volume = 45 | pages = 134–138 |bibcode = 2008Metro..45..134E |doi = 10.1088/0026-1394/45/2/002 | issue = 2}}</ref> | |||
===Expressing a physical value in terms of another unit===<!-- This section is linked from [[Watt-hour]] --> | |||
[[Conversion of units]] involves comparison of different standard physical values, either of a single physical quantity or of a physical quantity and a combination of other physical quantities. | |||
Starting with: | |||
:<math>Z = n_i \times [Z]_i</math> | |||
just replace the original unit <math>[Z]_i</math> with its meaning in terms of the desired unit <math>[Z]_j</math>, e.g. if <math>[Z]_i = c_{ij} \times [Z]_j</math>, then: | |||
:<math>Z = n_i \times (c_{ij} \times [Z]_j) = (n_i \times c_{ij}) \times [Z]_j</math> | |||
Now <math>n_i</math> and <math>c_{ij}</math> are both numerical values, so just calculate their product. | |||
Or, which is just mathematically the same thing, multiply ''Z'' by unity, the product is still ''Z'': | |||
:<math>Z = n_i \times [Z]_i \times ( c_{ij} \times [Z]_j/[Z]_i )</math> | |||
For example, you have an expression for a physical value ''Z'' involving the unit ''feet per second'' (<math>[Z]_i</math>) and you want it in terms of the unit ''miles per hour'' (<math>[Z]_j</math>): | |||
{{ordered list | |||
|1= Find facts relating the original unit to the desired unit: | |||
:1 mile = 5280 feet and 1 hour = 3600 seconds | |||
|2= Next use the above equations to construct a fraction that has a value of unity and that contains units such that, when it is multiplied with the original physical value, will cancel the original units: | |||
:<math>1 = \frac{1\,\mathrm{mi}}{5280\,\mathrm{ft}}\quad \mathrm{and}\quad 1 = \frac{3600\,\mathrm{s}}{1\,\mathrm{h}}</math> | |||
|3= Last, multiply the original expression of the physical value by the fraction, called a ''[[conversion factor]]'', to obtain the same physical value expressed in terms of a different unit. Note: since valid conversion factors are [[dimensionless]] and have a numerical value of [[one]], multiplying any physical quantity by such a conversion factor (which is 1) does not change that physical quantity. | |||
:<math> 52.8\,\frac{\mathrm{ft}}{\mathrm{s}} = | |||
52.8\,\frac{\mathrm{ft}}{\mathrm{s}} | |||
\frac{1\,\mathrm{mi}}{5280\,\mathrm{ft}} | |||
\frac{3600\,\mathrm{s}}{1\,\mathrm{h}} = | |||
\frac {52.8 \times 3600}{5280}\,\mathrm{mi/h} | |||
= 36\,\mathrm{mi/h}</math> | |||
}} | |||
Or as an example using the metric system, you have a value of fuel economy in the unit ''litres per 100 kilometres'' and you want it in terms of the unit ''microlitres per metre'': | |||
:<math> \mathrm{\frac{9\,\rm{L}}{100\,\rm{km}}} = | |||
\mathrm{\frac{9\,\rm{L}}{100\,\rm{km}}} | |||
\mathrm{\frac{1000000\,\rm{\mu L}}{1\,\rm{L}}} | |||
\mathrm{\frac{1\,\rm{km}}{1000\,\rm{m}}} = | |||
\frac {9 \times 1000000}{100 \times 1000}\,\mathrm{\mu L/m} = | |||
90\,\mathrm{\mu L/m}</math> | |||
==Real-world implications== | |||
One example of the importance of agreed units is the failure of the [[NASA]] [[Mars Climate Orbiter]], which was accidentally destroyed on a mission to Mars in September 1999 instead of entering orbit due to miscommunications about the value of forces: different computer programs used different units of measurement ([[Newton (unit)|newton]] versus [[pound force]]). Considerable amounts of effort, time, and money were wasted.<ref name=mixups> | |||
{{cite web | |||
|url=http://lamar.colostate.edu/~hillger/unit-mixups.html | |||
|title=Unit Mixups | |||
|publisher=US Metric Association | |||
}}</ref><ref> | |||
{{cite web | |||
|url=ftp://ftp.hq.nasa.gov/pub/pao/reports/1999/MCO_report.pdf | |||
|publisher=NASA | |||
|date=1999-11-10 | |||
|title=Mars Climate Orbiter Mishap Investigation Board Phase I Report | |||
}}</ref> | |||
On April 15, 1999 [[Korean Air]] cargo {{link-zh|Korean Air Cargo Flight 6316|大韓航空6316號班機空難|flight 6316}} from [[Shanghai]] to [[Seoul]] was lost due to the crew confusing tower instructions (in metres) and altimeter readings (in feet). Three crew and five people on the ground were killed. Thirty seven were injured.<ref> | |||
{{cite press release | |||
|url=http://www.ntsb.gov/pressrel/1999/990427.htm | |||
|title=Korean Air Flight 6316 | |||
|publisher=[[NTSB]] | |||
}}</ref><ref> | |||
{{cite web | |||
|url=http://aviation-safety.net/database/record.php?id=19990415-0 | |||
|title=Korean Air incident | |||
|publisher=Aviation Safety Net | |||
}}</ref> | |||
In 1983, a Boeing 767 (which came to be known as the [[Gimli Glider]]) ran out of fuel in mid-flight because of two mistakes in figuring the fuel supply of [[Air Canada]]'s first aircraft to use metric measurements.<ref> | |||
{{cite news | |||
|first=Richard | |||
|last=Witkin | |||
|authorlink= | |||
|coauthors= | |||
|title=Jet's Fuel Ran Out After Metric Conversion Errors | |||
|url=http://select.nytimes.com/search/restricted/article?res=F00F17F73B5D0C738FDDAE0894DB484D81 | |||
|quote=Air Canada said yesterday that its Boeing 767 jet ran out of fuel in mid-flight last week because of two mistakes in figuring the fuel supply of the airline's first aircraft to use metric measurements. After both engines lost their power, the pilots made what is now thought to be the first successful emergency ''dead stick'' landing of a commercial jetliner. | |||
|publisher=New York Times | |||
|date=July 30, 1983 | |||
|accessdate=2007-08-21 | |||
}}</ref> This accident is apparently the result of confusion both due to the simultaneous use of metric & Imperial measures as well as mass & volume measures. | |||
==See also== | |||
{{multicol}} | |||
* [[Chinese units of measurement]] | |||
* [[Indian weights and measures]] | |||
* [[Japanese units of measurement]] | |||
* [[List of humorous units of measurement]] | |||
* [[List of unusual units of measurement]] | |||
{{multicol-break}} | |||
* [[Spanish customary units]] | |||
* [[Taiwanese units of measurement]] | |||
* [[Unified Code for Units of Measure]] | |||
* [[United States customary units]] | |||
* [[Units conversion by factor-label]] | |||
{{multicol-end}} | |||
==Notes== | |||
{{Reflist|30em}} | |||
==External links== | |||
* Rowlett, Russ (2005) [http://www.unc.edu/~rowlett/units/ A Dictionary of Units of Measurement] - Russ Rowlett and the University of North Carolina at Chapel Hill | |||
* [http://ts.nist.gov/WeightsAndMeasures/Publications/H44-09.cfm NIST Handbook 44], ''Specifications, Tolerances, and Other Technical Requirements for Weighing and Measuring Devices'' | |||
* [http://www.bipm.org/en/si Official SI website] | |||
* [http://QuantitySystem.CodePlex.com/ Quantity System Framework] - Quantity System Library and Calculator for Units Conversions and Quantities predictions | |||
===Historical=== | |||
*[http://www.wdl.org/en/item/2847 "Arithmetic Conventions for Conversion Between Roman [i.e. Ottoman] and Egyptian Measurement"] is a manuscript from 1642, in Arabic, which is about units of measurement. | |||
===Legal=== | |||
* [http://www.irishstatutebook.ie/1996/en/act/pub/0027/ Ireland - Metrology Act 1996] | |||
* [http://www.law.cornell.edu/uscode/search/display.html?terms=unit%20measure&url=/uscode/html/uscode15/usc_sec_15_00000205----000-notes.html US - Authorized tables ] | |||
* {{UK-LEG|type=uksi|path=uksi/1995/1804|title=Units of Measurement Regulations 1995}} | |||
===Metric information and associations=== | |||
* [http://www.bipm.org/en/si BIPM] (official site) | |||
* [http://www.ukma.org.uk/ UK Metric Association] | |||
* [http://lamar.colostate.edu/~hillger US Metric Association] | |||
* [http://unitsofmeasure.org/ The Unified Code for Units of Measure] (UCUM) | |||
===Imperial measure information=== | |||
* [http://www.bwmaonline.com/ British Weights and Measures Association] | |||
{{systems of measurement}} | |||
{{DEFAULTSORT:Units Of Measurement}} | |||
[[Category:Units of measurement|*]] | |||
[[Category:Customary units of measurement|*]] | |||
[[Category:Human-based units of measurement|*]] | |||
[[Category:Measurement]] | |||
[[Category:Obsolete units of measurement|*]] | |||
[[Category:Systems of units|*]] | |||
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A unit of measurement is a definite magnitude of a physical quantity, defined and adopted by convention or by law, that is used as a standard for measurement of the same physical quantity.[1] Any other value of the physical quantity can be expressed as a simple multiple of the unit of measurement.
For example, length is a physical quantity. The metre is a unit of length that represents a definite predetermined length. When we say 10 metres (or 10 m), we actually mean 10 times the definite predetermined length called "metre".
The definition, agreement, and practical use of units of measurement have played a crucial role in human endeavour from early ages up to this day. Different systems of units used to be very common. Now there is a global standard, the International System of Units (SI), the modern form of the metric system.
In trade, weights and measures is often a subject of governmental regulation, to ensure fairness and transparency. The International Bureau of Weights and Measures (BIPM) is tasked with ensuring worldwide uniformity of measurements and their traceability to the International System of Units (SI). Metrology is the science for developing nationally and internationally accepted units of weights and measures.
In physics and metrology, units are standards for measurement of physical quantities that need clear definitions to be useful. Reproducibility of experimental results is central to the scientific method. A standard system of units facilitates this. Scientific systems of units are a refinement of the concept of weights and measures developed long ago for commercial purposes.
Science, medicine, and engineering often use larger and smaller units of measurement than those used in everyday life and indicate them more precisely. The judicious selection of the units of measurement can aid researchers in problem solving (see, for example, dimensional analysis).
In the social sciences, there are no standard units of measurement and the theory and practice of measurement is studied in psychometrics and the theory of conjoint measurement.
History
Mining Engineer (Excluding Oil ) Truman from Alma, loves to spend time knotting, largest property developers in singapore developers in singapore and stamp collecting. Recently had a family visit to Urnes Stave Church.
A unit of measurement is a standardised quantity of a physical property, used as a factor to express occurring quantities of that property. Units of measurement were among the earliest tools invented by humans. Primitive societies needed rudimentary measures for many tasks: constructing dwellings of an appropriate size and shape, fashioning clothing, or bartering food or raw materials.
The earliest known uniform systems of weights and measures seem to have all been created sometime in the 4th and 3rd millennia BC among the ancient peoples of Mesopotamia, Egypt and the Indus Valley, and perhaps also Elam in Persia as well.
Weights and measures are mentioned in the Bible (Leviticus 19:35-36). It is a commandment to be honest and have fair measures.
In "The Magna Carta" of 1215 (The Great Charter) with the seal of King John, put before him by the Barons of England, King John agreed in Clause 35 "There shall be one measure of wine throughout our whole realm, and one measure of ale and one measure of corn--namely, the London quart;--and one width of dyed and russet and hauberk cloths--namely, two ells below the selvage..."[2]
Many systems were based on the use of parts of the body and the natural surroundings as measuring instruments. Our present knowledge of early weights and measures comes from many sources.
Systems of units
Mining Engineer (Excluding Oil ) Truman from Alma, loves to spend time knotting, largest property developers in singapore developers in singapore and stamp collecting. Recently had a family visit to Urnes Stave Church.
Traditional systems
Historically many of the systems of measurement which had been in use were to some extent based on the dimensions of the human body according to the proportions described by Marcus Vitruvius Pollio.Potter or Ceramic Artist Truman Bedell from Rexton, has interests which include ceramics, best property developers in singapore developers in singapore and scrabble. Was especially enthused after visiting Alejandro de Humboldt National Park. As a result, units of measure could vary not only from location to location, but from person to person.
Metric systems
A number of metric systems of units have evolved since the adoption of the original metric system in France in 1791. The current international standard metric system is the International System of Units. An important feature of modern systems is standardization. Each unit has a universally recognized size.
Both the Imperial units and US customary units derive from earlier English units. Imperial units were mostly used in the British Commonwealth and the former British Empire. US customary units are still the main system of measurement used in the United States despite Congress having legally authorized metric measure on 28 July 1866.[3] Some steps towards US metrication have been made, particularly the redefinition of basic US and imperial units to derive exactly from SI units. Since the international yard and pound agreement of 1959 the US and imperial inch is now defined as exactly 0.0254 m, and the US and imperial avoirdupois pound is now defined as exactly 453.59237 g.[4]
Natural systems
While the above systems of units are based on arbitrary unit values, formalised as standards, some unit values occur naturally in science. Systems of units based on these are called natural units. Similar to natural units, atomic units (au) are a convenient system of units of measurement used in atomic physics.
Also a great number of unusual and non-standard units may be encountered. These may include the Solar mass (2 x 1030 kg) and the Megaton (1,000,000 tons of TNT).
Legal control of weights and measures
Mining Engineer (Excluding Oil ) Truman from Alma, loves to spend time knotting, largest property developers in singapore developers in singapore and stamp collecting. Recently had a family visit to Urnes Stave Church. To reduce the incidence of retail fraud, many national statutes have standard definitions of weights and measures that may be used (hence "statute measure"), and these are verified by legal officers.
Base and derived units
Different systems of units are based on different choices of a set of fundamental units. The most widely used system of units is the International System of Units, or SI. There are seven SI base units. All other SI units can be derived from these base units.
For most quantities a unit is absolutely necessary to communicate values of that physical quantity. For example, conveying to someone a particular length without using some sort of unit is impossible, because a length cannot be described without a reference used to make sense of the value given.
But not all quantities require a unit of their own. Using physical laws, units of quantities can be expressed as combinations of units of other quantities. Thus only a small set of units is required. These units are taken as the base units. Other units are derived units. Derived units are a matter of convenience, as they can be expressed in terms of basic units. Which units are considered base units is a matter of choice.
The base units of SI are actually not the smallest set possible. Smaller sets have been defined. For example, there are unit setsTemplate:Which in which the electric and magnetic field have the same unit. This is based on physical laws that show that electric and magnetic field are actually different manifestations of the same phenomenon.
Calculations with units of measurements
Template:Howto
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He'll then officially launch the development on the market, often with publicity and advertisements in the main newspapers. A large growth may even benefit a media marketing campaign. There is also often a showroom, with models and showflats, the place the preview takes place. Normally attended by savy traders & experienced property consumers, as this is the place the most worth-for-cash choicest picks are to be had. The "early bird will get the worm". TheMidtown is a combined growth close to Hougang MRT. It is ex-Hougang Plazaand will comprise of flats built above commercial shops, duplexrestaurants and a supermarket. VVIP Preview Soon! Register Now. Here's the start to how we will start our journey as investors utilizing property ownership to create a source of passive income.
The Peak @ Cairnhill - is the following upcoming Residential condominium in Singapore District 9. It's a Uncommon Freehold Growth that will outshine the Learn Extra b) Singapore Everlasting Residents (SPR) who already personal # 1 or extra residential properties would have to pay ABSD of three% on the acquisition or acquisition of another residential property. SGDeveloper.com showcase unique developer new properties launches in Singapore or overseas. Our workforce of skilled real estate consultants from numerous companies will assist you in securing your new dream home or in your property funding wants. N ew Apartment City Vista Tanah Merah Launch 2013 Wishing you the very best in your search for that preferrred new launch property in Singapore! Click on here to learn property market information
BuyRentSingaporeProperty.com is dedicated in providing the newest residential launches, Developer's sales, new launches, resale, HIGH projects and rental of properties in Singapore. Then there are new launch property condos within the mid-tier range. These are sometimes in the neighborhood of the town fringe, in areas comparable to Newton and Novena Tanjong Rhu. These new launch projects are fashionable because of their proximity to the town center, where the business and entertainment facilities and all of the facilities they provide, yet they are often cheaper than the Metropolis core region initiatives. Why submit cheques to register for brand new property launches in Singapore? Riversails Apartment @ Higher Serangoon LakeVille @ Jurong Lakeside Apartment by MCL Ferra Condo @ Leonie Hill
Lille has been very environment friendly in each aspect of their work. To start with, she did very detailed calculations concerning the buying and selling process. She obviously is aware of her work very nicely as she additionally highlighted and smoothed out quite a lot of issues that I am not even aware of as a seller.
Mere hours after being adopted by an Ohio family, a Saint Bernard named Hercules chased away an alleged burglar from his new commercial property launch in singapore [sell] home, in keeping with the Hillsboro Occasions-GazetteThe suspect had reportedly lower telephone and cable wires within the neighborhood, and was trying to enter the family's basement from the bottom of the house when Hercules started growling after which chased the person out of the yard. Read the full story right here You should utilize this listing to plan for future new launches, in addition to preserve observe of all existing outstanding launches in Singapore (new and outdated). Low-income families might be getting $four million in assist from the government and public transport operators in Singapore to cope with an upcoming fare hike Forestville EC @ Woodlands
A person needs a license to stroll around nude in his/her property. It's required that one should pay a property tax on their canine, in Rocky Mount. Nobody might set hearth to a different individual's property with out prior permission. Canine will need to have a allow signed by the mayor to be able to congregate in groups of three or extra on private property. GEYLANG Phoenix Land (Singapore) Pte Ltd 62 1 98.4 Feb-12 173 WATERTOWN PUNGGOL CENTRAL Emerald Star Pte Ltd / FC Retail Trustee Pte Ltd 992 8 99.2 18-Jan-12 174 THE NAUTICAL JALAN SENDUDOK Hao Yuan Investment Pte Ltd 435 5 98.9 17-Dec-11 one hundred seventy five IDYLLIC SUITES LORONG 30 Properties Pte Ltd fifty six 33 41.1 Aug-08 268 NATHAN RESIDENCES NATHAN ROAD Tat Aik Property A lady may not purchase a hat without her husband's permission in Owensboro.
blocks of 18-storey residential flats with complete 260 units, 1 Blk ofLow-rise reidential flat with total of 6 items with commercial at 1ststorey complete of 28 unit store models and 3 basement carpark lots. Totalof 337 models in 5 blocks of 18 storey condominium featuring sleekmodern design with sky garden by award successful architect Arc Studio& Urbanism. June 1st, 2013 Jewel @ Buangkok by CDL, 3mins from Buangkok MRT.Models promoting fast! Hurry safe your selection unit, Guide your showflatappointment Now. Qbay Residences guarantees an enviable Bayfront conceptlifestyle for the 630 items condominium in 8 blocks of 16 storey toweron a 99 12 months-leasehold website and fronting the event are two vastbeautiful waterscape - the Tampines Quarry Lake and BedokReservoir.
He'll then officially launch the development on the market, often with publicity and advertisements in the main newspapers. A large growth may even benefit a media marketing campaign. There is also often a showroom, with models and showflats, the place the preview takes place. Normally attended by savy traders & experienced property consumers, as this is the place the most worth-for-cash choicest picks are to be had. The "early bird will get the worm". TheMidtown is a combined growth close to Hougang MRT. It is ex-Hougang Plazaand will comprise of flats built above commercial shops, duplexrestaurants and a supermarket. VVIP Preview Soon! Register Now. Here's the start to how we will start our journey as investors utilizing property ownership to create a source of passive income.
The Peak @ Cairnhill - is the following upcoming Residential condominium in Singapore District 9. It's a Uncommon Freehold Growth that will outshine the Learn Extra b) Singapore Everlasting Residents (SPR) who already personal # 1 or extra residential properties would have to pay ABSD of three% on the acquisition or acquisition of another residential property. SGDeveloper.com showcase unique developer new properties launches in Singapore or overseas. Our workforce of skilled real estate consultants from numerous companies will assist you in securing your new dream home or in your property funding wants. N ew Apartment City Vista Tanah Merah Launch 2013 Wishing you the very best in your search for that preferrred new launch property in Singapore! Click on here to learn property market information
BuyRentSingaporeProperty.com is dedicated in providing the newest residential launches, Developer's sales, new launches, resale, HIGH projects and rental of properties in Singapore. Then there are new launch property condos within the mid-tier range. These are sometimes in the neighborhood of the town fringe, in areas comparable to Newton and Novena Tanjong Rhu. These new launch projects are fashionable because of their proximity to the town center, where the business and entertainment facilities and all of the facilities they provide, yet they are often cheaper than the Metropolis core region initiatives. Why submit cheques to register for brand new property launches in Singapore? Riversails Apartment @ Higher Serangoon LakeVille @ Jurong Lakeside Apartment by MCL Ferra Condo @ Leonie Hill
Units as dimensions
Any value of a physical quantity is expressed as a comparison to a unit of that quantity. For example, the value of a physical quantity Z is expressed as the product of a unit [Z] and a numerical factor:
- For example, "2 candlesticks" Z = 2 [candlestick].
![{\displaystyle Z=n\times [Z]=n[Z].}](https://wikimedia.org/api/rest_v1/media/math/render/svg/ed8877593e54d9a6ad269262e47041b7e4c8ea58)
The multiplication sign is usually left out, just as it is left out between variables in scientific notation of formulas. The conventions used to express quantities is referred to as quantity calculus. In formulas the unit [Z] can be treated as if it were a specific magnitude of a kind of physical dimension: see dimensional analysis for more on this treatment.
Units can only be added or subtracted if they are the same type; however units can always be multiplied or divided, as George Gamow used to explain:
- "2 candlesticks" times "3 cabdrivers" = 6 [candlestick][cabdriver].
A distinction should be made between units and standards. A unit is fixed by its definition, and is independent of physical conditions such as temperature. By contrast, a standard is a physical realization of a unit, and realizes that unit only under certain physical conditions. For example, the metre is a unit, while a metal bar is a standard. One metre is the same length regardless of temperature, but a metal bar will be exactly one metre long only at a certain temperature.
Guidelines
- Treat units algebraically. Only add like terms. When a unit is divided by itself, the division yields a unitless one. When two different units are multiplied, the result is a new unit, referred to by the combination of the units. For instance, in SI, the unit of speed is metres per second (m/s). See dimensional analysis. A unit can be multiplied by itself, creating a unit with an exponent (e.g. m2/s2). Put simply, units obey the laws of indices. (See Exponentiation.)
- Some units have special names, however these should be treated like their equivalents. For example, one newton (N) is equivalent to one kg·m/s2. Thus a quantity may have several unit designations, for example: the unit for surface tension can be referred to as either N/m (newtons per metre) or kg/s2 (kilograms per second squared). Whether these designations are equivalent is disputed amongst metrologists.[5]
Expressing a physical value in terms of another unit
Conversion of units involves comparison of different standard physical values, either of a single physical quantity or of a physical quantity and a combination of other physical quantities.
Starting with:
![{\displaystyle Z=n_{i}\times [Z]_{i}}](https://wikimedia.org/api/rest_v1/media/math/render/svg/9382a912ccadecfbe407dd9d2feec9b83febe4c0)
just replace the original unit with its meaning in terms of the desired unit , e.g. if , then:
![{\displaystyle [Z]_{i}}](https://wikimedia.org/api/rest_v1/media/math/render/svg/4c2e8f9c6283ef4fd7440576f12b3a002e33cc77)
![{\displaystyle [Z]_{j}}](https://wikimedia.org/api/rest_v1/media/math/render/svg/847ac5e13a07a2784aec0cd0f809a2853097580a)
![{\displaystyle [Z]_{i}=c_{ij}\times [Z]_{j}}](https://wikimedia.org/api/rest_v1/media/math/render/svg/d39d68c50a6f4eda1abeacd4a2a60c4f001cd19c)
![{\displaystyle Z=n_{i}\times (c_{ij}\times [Z]_{j})=(n_{i}\times c_{ij})\times [Z]_{j}}](https://wikimedia.org/api/rest_v1/media/math/render/svg/dd906cc1b06feb5974f2df92ddbad412489f41ae)
Now and are both numerical values, so just calculate their product.
Or, which is just mathematically the same thing, multiply Z by unity, the product is still Z:
![{\displaystyle Z=n_{i}\times [Z]_{i}\times (c_{ij}\times [Z]_{j}/[Z]_{i})}](https://wikimedia.org/api/rest_v1/media/math/render/svg/8f15189d031793d2d77b3a9337e805c69f3ca8f8)
For example, you have an expression for a physical value Z involving the unit feet per second () and you want it in terms of the unit miles per hour ():
Or as an example using the metric system, you have a value of fuel economy in the unit litres per 100 kilometres and you want it in terms of the unit microlitres per metre:
Real-world implications
One example of the importance of agreed units is the failure of the NASA Mars Climate Orbiter, which was accidentally destroyed on a mission to Mars in September 1999 instead of entering orbit due to miscommunications about the value of forces: different computer programs used different units of measurement (newton versus pound force). Considerable amounts of effort, time, and money were wasted.[6][7]
On April 15, 1999 Korean Air cargo Template:Link-zh from Shanghai to Seoul was lost due to the crew confusing tower instructions (in metres) and altimeter readings (in feet). Three crew and five people on the ground were killed. Thirty seven were injured.[8][9]
In 1983, a Boeing 767 (which came to be known as the Gimli Glider) ran out of fuel in mid-flight because of two mistakes in figuring the fuel supply of Air Canada's first aircraft to use metric measurements.[10] This accident is apparently the result of confusion both due to the simultaneous use of metric & Imperial measures as well as mass & volume measures.
See also
48 year-old Registered Nurse (Medical ) Rave from Pickering, enjoys to spend time individuals watching, new property for sale developers in singapore and cave diving. Finished a cruise liner experience that included passing by Chan Chan Archaeological Zone.
- Chinese units of measurement
- Indian weights and measures
- Japanese units of measurement
- List of humorous units of measurement
- List of unusual units of measurement
40 year old Supply and Circulation Manager Courtney from Aberdeen, has several pursuits including bmx, property developers in new project launch singapore and actions. Finds travel a wonderful experience after visiting Central Sikhote-Alin.
- Spanish customary units
- Taiwanese units of measurement
- Unified Code for Units of Measure
- United States customary units
- Units conversion by factor-label
Trying to invest in Singapore Actual Property , or are you attempting to promote, hire, invest, buy buy a Singapore property ? Properly then, you may have come to the fitting place in your seek for Singapore properties. Here, we are going to aid you find your dream Singapore property from our market itemizing of 1000's of Singapore properties in our Singapore real property database.
Overseas particular person who want to buy/ purchase a Restricted residential property in Sentosa Cove can acquire fast observe approval from Singapore Land Dealing Unit. Overseas particular person who want to purchase/ acquire a Restricted residential property in Sentosa Cove can apply for a long term social visit move underneath this Scheme to facilitate entry into Singapore. Foreign individual who want to apply for permanent residency in Singapore can contact SLA or MAS permitted institutions. The place you're shopping for property which is below development, the Singapore Academyof Regulation will maintain a portion of the acquisition monies as stakeholders till the expiryof the defects legal responsibility interval supplied in the Agreement/Contract. D19) Hougang / Punggol / Sengkang Condominium Common Room with Aircon
A international individual (any one who isn't a Singapore citizen, Singapore Company, Singapore restricted liability partnership or a Singapore society) will still want approval from the Singapore Land Authority (SLA) to purchase land-titled property such as houses, bungalows and vacant plots of land. Housing Improvement Board Properties SINGAPORE NON-PUBLIC RESIDENTIAL PROPERTIES Singapore firm; Singapore society. We provide invaluable services to expats who are considering relocation to Singapore For every kind of Singapore property related providers, we're there to obtain your name. You are positive to get one of the best Singapore properties with our help. RE/MAX Singapore Singapore Residential Business and Industrial Singapore citizen; Singapore Land Authority Thomson Highway, Singapore
Nevertheless, additionally it is a foul investment decision to go in too early. For instance you buy a property near one of the new MRT station location at the Thomson line. Because it takes 10 years to be accomplished, you might need difficulties renting that place out to pay off your mortgage payments. In addition, 10 years is a long time when something can occur including recession, new properties being introduced, modifications in interest rates etc. All these can have an adversarial impact on your property funding.
First, there are generally more rental transactions than gross sales transactions, to permit AV to be determined for every property based on comparable properties. Second, actions in sale costs are extra unstable than rentals. Therefore, using rental transactions to derive the AV helps to maintain property tax extra steady for property owners. If you are shopping for or trying to hire a property. It's tiring to call up individual property agent, prepare appointments, coordinate timing and to go for individual property viewing. What most individuals do is to have a property agent representing them who will organize and coordinate the viewings for all of the properties out there based mostly in your requirements & most well-liked timing. Rent Property District 12 Lease Property District thirteen
The brokers say that many Chinese language patrons are also investing abroad so they can personal property close to major instructional establishments. Some are buying houses close to top faculties — despite the fact that their youngsters are so little they can not walk but. Greater than 80 % of rich Chinese need to ship their children overseas to school, based on the Hurun Report, a Shanghai-based mostly publication. Chinese language patrons sometimes used to pick up properties within the $1 to $5 million vary in New York, typically shopping for two and three at a time for funding purposes, the brokers mentioned. Monika Tu, a dealer at high-end real estate agency Black Diamondz Property Concierge in Sydney, says that over the previous yr mainland Chinese language have develop into 80 % of her firm's business. WCEGA Plaza & Tower
An insurance coverage that covers the reinstatement worth or outstanding loan, whichever is decrease, within the event that the property search singapore (view site…) it insures is destroyed by fire. The coverage does not embody dwelling renovations, moveable household contents and personal belongings. Mortgage Insurance Credit bureau checks (e.g., Good payment data for bank cards / previous or existing loans, no previous blemishes corresponding to discharged bankrupts) A sign by the financial institution of the quantity of mortgage that you are eligible for. Nonetheless, an AIP doesn't constitute a binding loan offer. Additional checks and situations may be imposed by the financial institution, and the phrases of the formal supply will even rely upon the property that you simply intend to buy. Freehold / leasehold (999 years / 99 years)
Notes
43 year old Petroleum Engineer Harry from Deep River, usually spends time with hobbies and interests like renting movies, property developers in singapore new condominium and vehicle racing. Constantly enjoys going to destinations like Camino Real de Tierra Adentro.
External links
- Rowlett, Russ (2005) A Dictionary of Units of Measurement - Russ Rowlett and the University of North Carolina at Chapel Hill
- NIST Handbook 44, Specifications, Tolerances, and Other Technical Requirements for Weighing and Measuring Devices
- Official SI website
- Quantity System Framework - Quantity System Library and Calculator for Units Conversions and Quantities predictions
Historical
- "Arithmetic Conventions for Conversion Between Roman [i.e. Ottoman] and Egyptian Measurement" is a manuscript from 1642, in Arabic, which is about units of measurement.
Legal
Metric information and associations
- BIPM (official site)
- UK Metric Association
- US Metric Association
- The Unified Code for Units of Measure (UCUM)
Imperial measure information
Template:Systems of measurement
- ↑ Template:VIM3rd.
- ↑ [1]Template:Dead link
- ↑ Template:Cite web as amended by Public Law 110–69 dated August 9, 2007
- ↑ Template:Cite web
- ↑ One of the biggest reasons investing in a Singapore new launch is an effective things is as a result of it is doable to be lent massive quantities of money at very low interest rates that you should utilize to purchase it. Then, if property values continue to go up, then you'll get a really high return on funding (ROI). Simply make sure you purchase one of the higher properties, reminiscent of the ones at Fernvale the Riverbank or any Singapore landed property Get Earnings by means of Renting
In its statement, the singapore property listing - website link, government claimed that the majority citizens buying their first residence won't be hurt by the new measures. Some concessions can even be prolonged to chose teams of consumers, similar to married couples with a minimum of one Singaporean partner who are purchasing their second property so long as they intend to promote their first residential property. Lower the LTV limit on housing loans granted by monetary establishments regulated by MAS from 70% to 60% for property purchasers who are individuals with a number of outstanding housing loans on the time of the brand new housing purchase. Singapore Property Measures - 30 August 2010 The most popular seek for the number of bedrooms in Singapore is 4, followed by 2 and three. Lush Acres EC @ Sengkang
Discover out more about real estate funding in the area, together with info on international funding incentives and property possession. Many Singaporeans have been investing in property across the causeway in recent years, attracted by comparatively low prices. However, those who need to exit their investments quickly are likely to face significant challenges when trying to sell their property – and could finally be stuck with a property they can't sell. Career improvement programmes, in-house valuation, auctions and administrative help, venture advertising and marketing, skilled talks and traisning are continuously planned for the sales associates to help them obtain better outcomes for his or her shoppers while at Knight Frank Singapore. No change Present Rules
Extending the tax exemption would help. The exemption, which may be as a lot as $2 million per family, covers individuals who negotiate a principal reduction on their existing mortgage, sell their house short (i.e., for lower than the excellent loans), or take part in a foreclosure course of. An extension of theexemption would seem like a common-sense means to assist stabilize the housing market, but the political turmoil around the fiscal-cliff negotiations means widespread sense could not win out. Home Minority Chief Nancy Pelosi (D-Calif.) believes that the mortgage relief provision will be on the table during the grand-cut price talks, in response to communications director Nadeam Elshami. Buying or promoting of blue mild bulbs is unlawful.
A vendor's stamp duty has been launched on industrial property for the primary time, at rates ranging from 5 per cent to 15 per cent. The Authorities might be trying to reassure the market that they aren't in opposition to foreigners and PRs investing in Singapore's property market. They imposed these measures because of extenuating components available in the market." The sale of new dual-key EC models will even be restricted to multi-generational households only. The models have two separate entrances, permitting grandparents, for example, to dwell separately. The vendor's stamp obligation takes effect right this moment and applies to industrial property and plots which might be offered inside three years of the date of buy. JLL named Best Performing Property Brand for second year running
The data offered is for normal info purposes only and isn't supposed to be personalised investment or monetary advice. Motley Fool Singapore contributor Stanley Lim would not personal shares in any corporations talked about. Singapore private home costs increased by 1.eight% within the fourth quarter of 2012, up from 0.6% within the earlier quarter. Resale prices of government-built HDB residences which are usually bought by Singaporeans, elevated by 2.5%, quarter on quarter, the quickest acquire in five quarters. And industrial property, prices are actually double the levels of three years ago. No withholding tax in the event you sell your property. All your local information regarding vital HDB policies, condominium launches, land growth, commercial property and more
There are various methods to go about discovering the precise property. Some local newspapers (together with the Straits Instances ) have categorised property sections and many local property brokers have websites. Now there are some specifics to consider when buying a 'new launch' rental. Intended use of the unit Every sale begins with 10 p.c low cost for finish of season sale; changes to 20 % discount storewide; follows by additional reduction of fiftyand ends with last discount of 70 % or extra. Typically there is even a warehouse sale or transferring out sale with huge mark-down of costs for stock clearance. Deborah Regulation from Expat Realtor shares her property market update, plus prime rental residences and houses at the moment available to lease Esparina EC @ Sengkang - ↑ Template:Cite web
- ↑ Template:Cite web
- ↑ Template:Cite press release
- ↑ Template:Cite web
- ↑ Template:Cite news