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Why is a meter rule used to measure the initial length of a bar?
The length of a meter was originally determined with a metal reference, keep to this day in Paris, France.
How many meters in a bar?
- The meter is a unit of length, the bar a unit of pressure.- If you think to the object bar the length is very variable
What are the three intermediate definitions of the meter between 1793 and 1983?
The meter was defined in 1792 as 1/10,000,000 of the distance between the North Pole and the equator on a line running through Paris, France. The standard length of a meter was later changed to be the distance between two fine lines engraved on a bar of platinum and iridium alloy. The next definition was based on the wavelength of light emitted by an isotope of the element krypton. The present definition, in use since 1983, is the distance light travels in a vacuum during approximately one three hundred millionths of a second (1/299,792,458 sec).
What standard conditions does a gold bar have to meet?
A gold bar must meet the standard conditions of manufacture, labeling, and record keeping. A gold bar is then measured by the scale of troy ounces to determine its value.
What units are used when measuring pressure?
They are Bar, PSI, Meter, Kpa & N/m2
Why is a meter rule used to measure the initial length of a bar?
The length of a meter was originally determined with a metal reference, keep to this day in Paris, France.
The meter is defined as the distance traveled by light in 299792458th of a second.Why did not people choose some easier number such as 130000000th of a second.Why not 1 second?
The meter existed before we knew the speed of light exactly, and had a different definition. The original definition was that a meter was one ten-millionth of the distance between the North Pole and equator, travelling via Paris. A prototype bar was made to represent this distance, and became the official meter. (At the same time a one kilogram bar was created, which is still the official definition of the kilogram, but I digress). A bar is not possible to measure to 100% accuracy. Furthermore, the standard units should, in principle, be measurable by anybody, anywhere. (Energy is related to water, time to caesium, amps to electrons, etc... the kilo is the odd one out!) This isn't possible with a meter rule kept somewhere in Paris. In any case, the decision was made in 1983 to fix the meter to the speed of light. One 299792458th was the closest to the original meter bar, so that was the number chosen.
Irredeemably the most corrosion resistant metal 77 was allloyed with pt to make the standard metal bar of Paris?
Iridium
What is a tuple meter?
Tuple meter may be a misspelling or a confusion between "duple" meter and "triple" meter, which refer to pieces of music with 2 beats to the bar and 3 beats to the bar respectively.
What is a famous bar in Paris?
Willi's
Where is the standard of measurement kept?
There are several standards of measurement: weight, length, time to name a few. The standard for weight is the kilogram. The standard was made in London and has been stored in Paris since 1889. See this NPR article for a recent update (8/20/2009): http://www.npr.org/templates/story/story.php?storyId=112003322 The standard for length is the meter, or metre. Until 1983, this standard was a platinum-iridium bar that rested next to the kilogram standard at the French Academy of Sciences. In 1983, the metre was redefined as the distance travelled by light in free space in 1⁄299,792,458 of a second. http://en.wikipedia.org/wiki/Meter The standard for time is the second. "Currently, the international unit of time, the second, is defined in terms of radiation emitted by caesium atoms." http://en.wikipedia.org/wiki/Time Most standards are abstracts, with qualities or characteristics not affixed to a particular object or instance, such as a number. These standards have no place to be kept, except in the imagination of those who conceive of them.
Where is the headquarters for the organization that maintains SI standards?
The only standard unit that has a physical presence is the unit if mass. The Kilogram. It is kept in Paris.The metre was originally a length of bar also kept in Paris, this, as a standard, has now been superseded though the bar still exists.add Currently work is under way to manufacture almost perfectly spherical spheres (made of Silicon I think?) and the number of atoms of Si in these spheres will be known to a high degree of precision.Many standards laboratories still have physical blobs of length and mass for convenience in transferring the Standards to Industry.
What is the formula to calculate steel tmt bar weight per meter sow with example?
Formula for steel bar weight per meter = D2/162 where D is diameter of bar
How much does a standard 7' weight lifting bar weigh?
A standard bar weights 20 pounds.
A Bar graph for the population of Paris?
sluts and pussies
What is gold brick?
gold brick / gold bar . A gold bar is a quantity of refined metallic gold of any shape that is made by a bar producer meeting standard conditions of manufacture, labeling, and record keeping.
Standard size of a bar countertop?
What's the standard size for counter top bar
