Changes

==Etymology==

==Etymology==

[http://nordan.daynal.org/wiki/index.php?title=English#ca._1100-1500_.09THE_MIDDLE_ENGLISH_PERIOD Middle English] wight, weght, from [http://nordan.daynal.org/wiki/index.php?title=English#ca._600-1100.09THE_OLD_ENGLISH.2C_OR_ANGLO-SAXON_PERIOD Old English] wiht; akin to Old Norse vætt weight, Old English wegan to weigh

[https://nordan.daynal.org/wiki/index.php?title=English#ca._1100-1500_.09THE_MIDDLE_ENGLISH_PERIOD Middle English] wight, weght, from [https://nordan.daynal.org/wiki/index.php?title=English#ca._600-1100.09THE_OLD_ENGLISH.2C_OR_ANGLO-SAXON_PERIOD Old English] wiht; akin to Old Norse vætt weight, Old English wegan to weigh

*Date: before [http://www.wikipedia.org/wiki/11th_Century 12th century]

*Date: before [https://www.wikipedia.org/wiki/11th_Century 12th century]

==Definitions==

==Definitions==

*1 a : the amount that a [[thing]] weighs b (1) : the [[standard]] or established amount that a thing should weigh (2) : one of the classes into which contestants in a [[sports]] event are divided according to [[body]] weight (3) : poundage required to be carried by a horse in a handicap race

*1 a : the amount that a [[thing]] weighs b (1) : the [[standard]] or established amount that a thing should weigh (2) : one of the classes into which contestants in a [[sports]] event are divided according to [[body]] weight (3) : poundage required to be carried by a horse in a handicap race

Nevertheless, the Earth's gravitational field can vary by as much as 0.5% at different locations on Earth. These variations alter the [[relationship]] between weight and mass, and must be taken into account in high precision weight [[measurements]] that are intended to indirectly measure mass. To eliminate this variation, when the weight of objects is used in [[Business|commerce]], the [[value]] given is what the objects would weigh at a nominal [[standard]] gravitational acceleration of 9.80665 m/s2 (approx. 32.174 ft/s2). Spring scales, which measure local weight, must be calibrated at the location at which the objects will be used to show this standard weight, to be legal for commerce.

Nevertheless, the Earth's gravitational field can vary by as much as 0.5% at different locations on Earth. These variations alter the [[relationship]] between weight and mass, and must be taken into account in high precision weight [[measurements]] that are intended to indirectly measure mass. To eliminate this variation, when the weight of objects is used in [[Business|commerce]], the [[value]] given is what the objects would weigh at a nominal [[standard]] gravitational acceleration of 9.80665 m/s2 (approx. 32.174 ft/s2). Spring scales, which measure local weight, must be calibrated at the location at which the objects will be used to show this standard weight, to be legal for commerce.

The use of "weight" for "mass" also persists in some scientific terminology – for example, the [[chemical]] terms "atomic weight", "molecular weight", and "formula weight", can still be found rather than the preferred "[http://en.wikipedia.org/wiki/Atomic_mass atomic mass]" etc.

The use of "weight" for "mass" also persists in some scientific terminology – for example, the [[chemical]] terms "atomic weight", "molecular weight", and "formula weight", can still be found rather than the preferred "[https://en.wikipedia.org/wiki/Atomic_mass atomic mass]" etc.

The difference between mass and weight is apparent when, for example:

The difference between mass and weight is apparent when, for example:

*objects are compared in different gravitational fields, such as away from the Earth's surface. For example, on the surface of the Moon, gravity is only about one-sixth as strong as on the surface of the Earth. A one-kilogram mass is still a one-kilogram mass (as mass is an intrinsic property of the object) but the downward force due to gravity is only one-sixth of what the object would experience on Earth.

*objects are compared in different gravitational fields, such as away from the Earth's surface. For example, on the surface of the Moon, gravity is only about one-sixth as strong as on the surface of the Earth. A one-kilogram mass is still a one-kilogram mass (as mass is an intrinsic property of the object) but the downward force due to gravity is only one-sixth of what the object would experience on Earth.

*an object is immersed in a liquid or gas. For instance, a brick weighs less when suspended in water, even though its mass is unchanged, and a helium balloon in the atmosphere appears to have negative weight, even though its mass is positive.[http://en.wikipedia.org/wiki/Weight]

*an object is immersed in a liquid or gas. For instance, a brick weighs less when suspended in water, even though its mass is unchanged, and a helium balloon in the atmosphere appears to have negative weight, even though its mass is positive.[https://en.wikipedia.org/wiki/Weight]

[[Category: Physics]]

[[Category: Physics]]