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The '''foot–pound–second system''' or '''FPS system''' is a system of units built on the three fundamental units [[foot (unit)|foot]] for length, [[pound (mass)|(avoirdupois) pound]] for either mass or force (see below) and [[second]] for time.<ref name=cardarelli>{{citation |title=Encyclopaedia of Scientific Units, Weights and Measures : Their SI Equivalences and Origins |last=Cardarelli |first=François |publisher=Springer |year=2003 | isbn=978-1-85233-682-0 |chapter=The Foot–Pound–Second (FPS) System |pages=51–55}}.</ref> | |||
== Variants == | |||
Collectively, the variants of the FPS system were the most common system in technical publications in English until the middle of the 20th century.<ref name=cardarelli/> | |||
{{anchor|Stroud}}Errors can be avoided and translation between the systems facilitated by labelling all physical dimensions consistently with their units. Especially in the context of the FPS system this is sometimes known as the '''Stroud system''' after [[William Stroud]], who popularized it.<ref>{{citation |title=The Stroud system of teaching dynamics |last1=Henderson |first1=James B. |last2=Godfrey |first2=C. |journal=The Mathematical Gazette |volume=12 |number=170 |year=1924 |pages=99–105 |jstor=3604647}}.</ref> | |||
{{GravEngAbs|system=English}} | |||
=== Pound as mass unit === | |||
{{anchor|mass}} | |||
When the pound is used as a unit of mass (often denoted as "pound-mass" and abbreviated as "lbm" to avoid confusion), the core of the coherent system is similar and functionally equivalent to the corresponding subsets of the [[International System of Units]] (SI), using kilogram, metre and second (MKS), and the earlier [[centimetre–gram–second system of units]] (CGS). | |||
In this sub-system, the unit of [[force]] is a derived unit known as the [[poundal]].<ref name=cardarelli/> | |||
:<math>1\,\text{pdl} = 1\,\text{lb}_m \cdot 1\,\frac{\text{ft}}{\text{s}^2}</math> | |||
In the context of the absolute FPS system, the pound-mass ({{lbm}}) is sometimes referred to simply as the pound (lb), although such use is discouraged in favor of the less ambiguous 'lbm' in disciples which use US customary units (such as the US aerospace industry). | |||
{{Cleanup|section|date=October 2011}} | |||
Everett (1861)<!--ref missing--> proposed the metric [[dyne]] and [[erg]] as the units of force and energy in the FPS system. | |||
Latimer Clark's (1891) "Dictionary of Measures"<!--ref missing--> contains ''celo'' (acceleration), ''vel'' or ''velo'' (velocity) and ''pulse'' (momentum) as proposed names for FPS absolute units.<!--definitions or explanations missing--> | |||
=== Pound-force as force unit === | |||
{{anchor|force}} | |||
The '''technical''' or '''gravitational FPS system''',<ref name=cr>[http://books.google.com/books?id=lEi8RU6Br6YC&lpg=PA5&pg=PA5 J. M. Coulson, J. F. Richardson, J. R. Backhurst, J. H. Harker: Coulson & Richardson's Chemical Engineering: Fluid flow, heat transfer, and mass transfer.]</ref> is a coherent variant of the FPS system that is most common among engineers in the United States. It takes the [[pound-force]] as a fundamental unit of force instead of the pound as a fundamental unit of mass. | |||
In this sub-system, the unit of mass is a derived unit known as the [[slug (unit)|slug]].<ref name=cardarelli/> | |||
:<math>1\,\text{slug} = 1\,\text{lb}_F \cdot 1\,\frac{\text{s}^2}{\text{ft}}</math> | |||
In the context of the gravitational FPS system, the pound-force ({{lbf}}) is almost universally simply referred to as the pound (lb). | |||
=== Pound as mass and force unit === | |||
{{anchor|weight}} | |||
Another variant of the FPS system uses both the pound-mass and the pound-force, but neither the slug nor the poundal. The resulting system is not coherent, lacking electrical or molar units, and is sometimes also known as the '''British engineering system''', although rarely used nowadays in the [[United Kingdom]].<ref name=cr/> | |||
== Other units == | |||
{{Cleanup|section|date=October 2011}} | |||
=== Molar units === | |||
The unit of substance in the FPS system is the pound-mole (lb-mol) = 273.16×10<sup>24</sup>. Until the SI decided to adopt the gram-mole, the mole was directly derived from the mass unit as (mass unit)/(atomic mass unit). The unit ({{lbf}}·s²/ft)-mol also appears in a former definition of the atmosphere. | |||
=== Electromagnetic units === | |||
The Electrostatic and Electromagnetic systems are derived from units of length and force, mainly. As such, these are ready extensions of any system of containing length, mass, time. Stephen Dresner<ref>{{cite book|last=Dresner|first=Stephen|title=Units of Measurement|year=1971|publisher=Hastings House|location=New York|pages=193–205}}</ref> gives the derived electrostatic and electromagnetic units in both the foot–pound–second and foot–slug–second systems. In practice, these are most associated with the centimetre–gram–second system. The 1929 "International Critical Tables" gives in the symbols and systems fpse = FPS electrostatic system and fpsm = FPS electromagnetic system. Under the conversions for charge, the following are given. The CRC Handbook of Chemistry and Physics 1979 (Edition 60), also lists fpse and fpsm as standard abbreviations. | |||
; Electromagnetic FPS (EMU, stat-) | |||
: 1 fpsm unit = 117.581866 cgsm unit (Biot-second) | |||
; Electrostatic FPS (ESU, ab-) | |||
: 1 fpse unit = 3583.8953 cgse unit (Franklin) | |||
: 1 fpse unit = 1.1954588×10<sup>−6</sup> abs coulomb | |||
=== Units of light === | |||
The ''[[candela|candle]]'' and the ''foot-candle'' were the first defined units of light, defined in the Metropolitan Gas Act (1860).<ref>{{cite book|last=Jerrard|first=H G|title=A Dictionary of Scientific Units|year=1985|publisher=Chapman and Hall|location=London|isbn=0412281007|pages=24}}</ref> The foot-candle is the intensity of light at one foot from a ''standard candle''. The units were internationally recognised in 1881, and adopted into the metric system.<ref>{{citation|first=Donald|last=Fenna|year=2003|title=Dictionary of weights and measures|isbn=978-0-19-860522-5}}</ref> | |||
== Conversions == | |||
Together with the fact that the term "weight" is used for the gravitational force in some technical contexts (physics, engineering) and for mass in others (commerce, law),<ref>[http://ts.nist.gov/WeightsAndMeasures/Metric/upload/fs376-b.pdf NIST Federal Standard 376B], p. 13.</ref> and that the distinction often does not matter in practice, the coexistence of variants of the FPS system causes confusion over the nature of the unit "pound". Its relation to international, metric units is expressed in kilograms, not newtons, though, and in earlier times it was defined by means of a mass prototype to be compared with a [[weighing scale|two-pan balance]] which is agnostic of local gravitational differences. | |||
In July 1959 the various national foot and avoirdupois pound standards were replaced by the international foot of precisely {{val|0.3048|u=m}} and the international pound of precisely {{val|0.45359237|u=kg}}, making conversion between the systems a matter of simple mathematics. The conversion for the poundal is given by 1 pdl = 1 lb·ft/s<sup>2</sup> = {{val|0.138254954376|ul=N}} (precisely).<ref name=cardarelli/> | |||
To convert between the absolute and gravitational FPS systems one needs to fix the [[standard gravity|standard acceleration]] ''g'' which connects the pound and the pound-force. | |||
:<math>1\,\text{lb}_F = 1\,\text{lb}_m\cdot g</math> | |||
While ''g'' strictly depends on one's location on the Earth surface, since 1901 in most contexts it is fixed conventionally at precisely ''g''<sub>0</sub> = {{val|9.80665|u=m/s2}} ≈ {{val|32.17405|u=ft/s2}}.<ref name=cardarelli/> Therefore the slug is about {{val|32.17405|u=lbm}} or {{val|14.593903|u=kg}}. | |||
==References== | |||
{{reflist}} | |||
{{DEFAULTSORT:Foot-pound-second system}} | |||
[[Category:Systems of units]] | |||
[[Category:Imperial units]] | |||
[[Category:Customary units of measurement in the United States]] | |||
Revision as of 21:09, 12 March 2013
The foot–pound–second system or FPS system is a system of units built on the three fundamental units foot for length, (avoirdupois) pound for either mass or force (see below) and second for time.[1]
Variants
Collectively, the variants of the FPS system were the most common system in technical publications in English until the middle of the 20th century.[1]
<Stroud>...</Stroud>Errors can be avoided and translation between the systems facilitated by labelling all physical dimensions consistently with their units. Especially in the context of the FPS system this is sometimes known as the Stroud system after William Stroud, who popularized it.[2]
Template:GravEngAbs
Pound as mass unit
<mass>...</mass>
When the pound is used as a unit of mass (often denoted as "pound-mass" and abbreviated as "lbm" to avoid confusion), the core of the coherent system is similar and functionally equivalent to the corresponding subsets of the International System of Units (SI), using kilogram, metre and second (MKS), and the earlier centimetre–gram–second system of units (CGS).
In this sub-system, the unit of force is a derived unit known as the poundal.[1]
In the context of the absolute FPS system, the pound-mass (Template:Lbm) is sometimes referred to simply as the pound (lb), although such use is discouraged in favor of the less ambiguous 'lbm' in disciples which use US customary units (such as the US aerospace industry).
Template:Cleanup Everett (1861) proposed the metric dyne and erg as the units of force and energy in the FPS system.
Latimer Clark's (1891) "Dictionary of Measures" contains celo (acceleration), vel or velo (velocity) and pulse (momentum) as proposed names for FPS absolute units.
Pound-force as force unit
<force>...</force>
The technical or gravitational FPS system,[3] is a coherent variant of the FPS system that is most common among engineers in the United States. It takes the pound-force as a fundamental unit of force instead of the pound as a fundamental unit of mass.
In this sub-system, the unit of mass is a derived unit known as the slug.[1]
In the context of the gravitational FPS system, the pound-force (Template:Lbf) is almost universally simply referred to as the pound (lb).
Pound as mass and force unit
<weight>...</weight>
Another variant of the FPS system uses both the pound-mass and the pound-force, but neither the slug nor the poundal. The resulting system is not coherent, lacking electrical or molar units, and is sometimes also known as the British engineering system, although rarely used nowadays in the United Kingdom.[3]
Other units
Molar units
The unit of substance in the FPS system is the pound-mole (lb-mol) = 273.16×1024. Until the SI decided to adopt the gram-mole, the mole was directly derived from the mass unit as (mass unit)/(atomic mass unit). The unit (Template:Lbf·s²/ft)-mol also appears in a former definition of the atmosphere.
Electromagnetic units
The Electrostatic and Electromagnetic systems are derived from units of length and force, mainly. As such, these are ready extensions of any system of containing length, mass, time. Stephen Dresner[4] gives the derived electrostatic and electromagnetic units in both the foot–pound–second and foot–slug–second systems. In practice, these are most associated with the centimetre–gram–second system. The 1929 "International Critical Tables" gives in the symbols and systems fpse = FPS electrostatic system and fpsm = FPS electromagnetic system. Under the conversions for charge, the following are given. The CRC Handbook of Chemistry and Physics 1979 (Edition 60), also lists fpse and fpsm as standard abbreviations.
- Electromagnetic FPS (EMU, stat-)
- 1 fpsm unit = 117.581866 cgsm unit (Biot-second)
- Electrostatic FPS (ESU, ab-)
- 1 fpse unit = 3583.8953 cgse unit (Franklin)
- 1 fpse unit = 1.1954588×10−6 abs coulomb
Units of light
The candle and the foot-candle were the first defined units of light, defined in the Metropolitan Gas Act (1860).[5] The foot-candle is the intensity of light at one foot from a standard candle. The units were internationally recognised in 1881, and adopted into the metric system.[6]
Conversions
Together with the fact that the term "weight" is used for the gravitational force in some technical contexts (physics, engineering) and for mass in others (commerce, law),[7] and that the distinction often does not matter in practice, the coexistence of variants of the FPS system causes confusion over the nature of the unit "pound". Its relation to international, metric units is expressed in kilograms, not newtons, though, and in earlier times it was defined by means of a mass prototype to be compared with a two-pan balance which is agnostic of local gravitational differences.
In July 1959 the various national foot and avoirdupois pound standards were replaced by the international foot of precisely Template:Val and the international pound of precisely Template:Val, making conversion between the systems a matter of simple mathematics. The conversion for the poundal is given by 1 pdl = 1 lb·ft/s2 = Template:Val (precisely).[1]
To convert between the absolute and gravitational FPS systems one needs to fix the standard acceleration g which connects the pound and the pound-force.
While g strictly depends on one's location on the Earth surface, since 1901 in most contexts it is fixed conventionally at precisely g0 = Template:Val ≈ Template:Val.[1] Therefore the slug is about Template:Val or Template:Val.
References
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.
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010. - ↑ Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010. - ↑ 3.0 3.1 J. M. Coulson, J. F. Richardson, J. R. Backhurst, J. H. Harker: Coulson & Richardson's Chemical Engineering: Fluid flow, heat transfer, and mass transfer.
- ↑ 20 year-old Real Estate Agent Rusty from Saint-Paul, has hobbies and interests which includes monopoly, property developers in singapore and poker. Will soon undertake a contiki trip that may include going to the Lower Valley of the Omo.
My blog: http://www.primaboinca.com/view_profile.php?userid=5889534 - ↑ 20 year-old Real Estate Agent Rusty from Saint-Paul, has hobbies and interests which includes monopoly, property developers in singapore and poker. Will soon undertake a contiki trip that may include going to the Lower Valley of the Omo.
My blog: http://www.primaboinca.com/view_profile.php?userid=5889534 - ↑ Many property agents need to declare for the PIC grant in Singapore. However, not all of them know find out how to do the correct process for getting this PIC scheme from the IRAS. There are a number of steps that you need to do before your software can be approved.
Naturally, you will have to pay a safety deposit and that is usually one month rent for annually of the settlement. That is the place your good religion deposit will likely be taken into account and will kind part or all of your security deposit. Anticipate to have a proportionate amount deducted out of your deposit if something is discovered to be damaged if you move out. It's best to you'll want to test the inventory drawn up by the owner, which can detail all objects in the property and their condition. If you happen to fail to notice any harm not already mentioned within the inventory before transferring in, you danger having to pay for it yourself.
In case you are in search of an actual estate or Singapore property agent on-line, you simply should belief your intuition. It's because you do not know which agent is nice and which agent will not be. Carry out research on several brokers by looking out the internet. As soon as if you end up positive that a selected agent is dependable and reliable, you can choose to utilize his partnerise in finding you a home in Singapore. Most of the time, a property agent is taken into account to be good if he or she locations the contact data on his website. This may mean that the agent does not mind you calling them and asking them any questions relating to new properties in singapore in Singapore. After chatting with them you too can see them in their office after taking an appointment.
Have handed an trade examination i.e Widespread Examination for House Brokers (CEHA) or Actual Property Agency (REA) examination, or equal; Exclusive brokers are extra keen to share listing information thus making certain the widest doable coverage inside the real estate community via Multiple Listings and Networking. Accepting a severe provide is simpler since your agent is totally conscious of all advertising activity related with your property. This reduces your having to check with a number of agents for some other offers. Price control is easily achieved. Paint work in good restore-discuss with your Property Marketing consultant if main works are still to be done. Softening in residential property prices proceed, led by 2.8 per cent decline within the index for Remainder of Central Region
Once you place down the one per cent choice price to carry down a non-public property, it's important to accept its situation as it is whenever you move in – faulty air-con, choked rest room and all. Get round this by asking your agent to incorporate a ultimate inspection clause within the possibility-to-buy letter. HDB flat patrons routinely take pleasure in this security net. "There's a ultimate inspection of the property two days before the completion of all HDB transactions. If the air-con is defective, you can request the seller to repair it," says Kelvin.
15.6.1 As the agent is an intermediary, generally, as soon as the principal and third party are introduced right into a contractual relationship, the agent drops out of the image, subject to any problems with remuneration or indemnification that he could have against the principal, and extra exceptionally, against the third occasion. Generally, agents are entitled to be indemnified for all liabilities reasonably incurred within the execution of the brokers´ authority.
To achieve the very best outcomes, you must be always updated on market situations, including past transaction information and reliable projections. You could review and examine comparable homes that are currently available in the market, especially these which have been sold or not bought up to now six months. You'll be able to see a pattern of such report by clicking here It's essential to defend yourself in opposition to unscrupulous patrons. They are often very skilled in using highly unethical and manipulative techniques to try and lure you into a lure. That you must also protect your self, your loved ones, and personal belongings as you'll be serving many strangers in your home. Sign a listing itemizing of all of the objects provided by the proprietor, together with their situation. HSR Prime Recruiter 2010 - ↑ NIST Federal Standard 376B, p. 13.