The metric system is Fundamental Did you know, that there have never been any old pre-metric measures for electricity? The USA has had to copy all its electrical units volt, ampere, watt, ohm from the metric system. Did you know, that computers are designed from their smallest parts using nanometres and micrometres? Their circuit boards and cases are then designed and built using millimetres.
Finally, the size of the screen and the size of the disks are dumbed down from millimetres to inches to avoid your anger at having to use a fully metric computer.
Did you know, that the metric system is now the fundamental basis for all of the world's old pre-metric measures? For example, that the USA has based the length of a foot, a yard, a chain, and a mile on metric standards since ?
Mendenhall, then Superintendent of Weights and Measures, with the approval of the Secretary of the Treasury, decided that the international metre and kilogram would in the future be regarded as the fundamental standards of length and mass in the United States, both for metric and customary weights and measures. Did you know, that in , by agreement between the English speaking nations, the inch was re-defined as exactly Now, whenever you refer to an inch and by extension also a foot, a yard, and a mile, you are really referring to a metric inch, a metric foot, a metric yard, and a metric mile.
Did you know, that the world standard railway gauge is now millimetres? Did you know, that the, so called, 12 inch and 10 inch vinyl records were designed to be millimetres and millimetres respectively? Did you know, that because the metric system is now so fundamental to all of the old pre-metric measures, the USA now finds itself in a position where economic realities, international standards, and the shortcomings of the old pre-metric methods force it to use the metric system daily for all of its activities?
The metric system is unique because it: is human in scale. For example: Your hand is about mm across if you include your thumb. For most men the width of their little fingernail is close to 10 mm. For most women the width of their fingernail on their long finger is close to 10 mm. Your hand span is between mm and mm. Women's walking pace is about mm. Men's stretched walking pace is about mm or 1 metre. A marching pace for both men and women is mm. Most people walk at about metres per minute.
The body mass of most women is between 50 kg and 80 kg. The body mass of most men is between 60 kg and 90 kg. The average height of men is 1. The average height of women is 1.
Most newborn babies are close to mm long. The lengths of most people's feet are close to mm. From the day we are born, we confront the metric system. Newborn babies have their mass determined on a set of scales almost immediately after their birth. Most babies are about 3. The reason that babies have their mass determined so quickly is so that medical staff can treat the baby with medicines if it becomes ill, and these medicines are dosed in milligrams per kilogram, or in micrograms per kilogram.
Sadly, however, there are mothers, grandmothers, sisters, cousins, and aunts who dumb down the baby's mass to pounds and ounces, possibly putting the health of their babies at risk.
The metric system is decimal The metric system uses the same decimal numbers that we use for counting and calculating. This means that you can do any metric system calculations on an ordinary calculator. Suppose you want some vinyl tiles for a bathroom floor that is 3. Note that your calculator is of little use here. Because the metric system is a decimal system, it has a simple set of conversion factors tens, hundreds and thousands that are consistent across all measurements. These are known as 'multiples of ten' or sometimes 'powers of ten'.
As you use the metric system, you will never have to deal with 2s, 3s, 4s, 12s, or 16s as you do with 2 pints in a quart; 3 feet in a yard; 4 quarters in a hundredweight; 12 inches in a foot; or 16 ounces in a pound. You don't have to remember any other strange numbers like cubic inches in a gallon USA , pounds in a long ton , feet in a mile or hundreds of other similar diversities.
Even with 'difficult' numbers such as thirds, the metric system allows you to treat them with ease. Suppose you want to divide a kilometre of wire into 3 equal parts. You now need to decide how accurate you want the three pieces to be.
If you decide on a precision of 1 millimetre, you could divide the original kilometre into 3 parts of If you require more precision, you could even choose micrometres. Clearly, the metric system allows you to decide on your exact levels of accuracy and precision. By the way, if someone suggests to you that the metric system is not good at vulgar fractions such as thirds, simply ask them to calculate in their heads a third of a mile in yards, feet, and inches to the nearest sixteenth of an inch or a third of a pound in ounces to the nearest pennyweight.
In practice, people find that metric dimensions are quite easy to subdivide using a range of factors, as it is easy to move to smaller sub-multiples of metric units. It is also more common in the metric world to use standardised preferred number sequences. For example, in the Australian and British building industries, design dimensions are usually multiples of millimetres. As a result, 2, 3, 4, 5, 6, 8, 10, 12, 15, 20, 24, 25, 30, 40, 50, 60, 75, , , , , or , can divide common building dimensions without any fractions of millimetres.
The metric system has prefixes Prefixes are short, convenient, unambiguous, easy-to-pronounce names and letter symbols for powers of ten. In the metric system, there are 20 of them. You can easily choose a unit of the right size for the jobs you do. Once you know the basic unit of a quantity that you want to measure, then it is easy for you to generate all the other names.
Suppose you want to measure a length and you know that in the metric system length uses the unit: metre. Then you would probably choose from this list of possibilities. Careful observers have noticed that metrication using millimetres is dramatically faster, cheaper, and smoother than metric conversion using centimetres. The use of centimetres, decimetres, centilitres, and decilitres has proved to be a major disadvantage to direct metrication.
This has been a particular problem in traditional women's activities such as cooking, nursing, primary school teaching, and sewing where the use of the centimetre is common. This means that you should avoid the prefixes, centi, deci, deca, and hecto. The prefixes of the metric system allow you to, quickly and easily, change from smaller to larger unit multiples. Changing between different multiples and sub-multiples of metric units is as easy as shifting a decimal point and changing the name of the prefix.
As an example, when you rewrite metres as 2. No arithmetic was necessary; it's a bit like rewriting metres as 2 thousand, three hundred, and forty metres. The metric system prefixes remarkably simplify calculations and reduce the time needed to perform them.
The most commonly used prefixes are: milli, used in millilitres, milligrams, and millimetres, and kilo, used in kilolitres, kilograms, and kilometres.
This means that in the whole metric system, there are only 16 prefix names to learn there are still only 20 prefix names if you include those used less often: centi, deci, deca, and hecto. Generally, the metric system tends not to need fractions. You might choose to use decimals exclusively, thus eliminating the clumsy vulgar or common fractions and the even clumsier mixed numbers.
Most people who use the metric system regularly tend to prefer to use decimal fractions, that is, if they use fractions at all. You can go beyond this. They are distinct and cannot be confused. In building and construction the centimetre will not be used. Since the mid s, builders in Australia have not needed to ever think about fractions, whether vulgar or common , mixed numbers, or even decimal fractions. The metric system was planned When you use the metric system, you are only using one single system of units.
Other measuring methods arose more or less at random from a multitude of historical sources. The metric system is simple and more logical than any previous methods of measurement ever known because it was logically planned from its beginning.
During the second half of the twentieth century most countries that had previously used traditional units adopted metric. Japan abandoned traditional units in and India started to adopt metric in the late s.
With Britain announcing its plans to go metric in , the rest of the Commonwealth from Australia to Zambia made plans for a metric conversion if they did not already have plans underway.
Even the USA has made a start on metrication. The metric system is important for British trade and therefore also for British jobs. Use of a common system of units facilitates cross-border collaboration in design, engineering, science and medicine. The further development of the metric system is international. The development of the metric system is governed by the Metre Convention ; which Britain signed in British scientists have contributed to the development of the metric system in the past and continue to do so.
A good grasp of measurement units such as temperature, mass and distance is fundamental to health and safety. There is currently great public concern about the growth of obesity in Britain. People who measure themselves in metric can quickly assess whether their BMI is healthy or not.
People who weigh themselves in stones and pounds and measure their height in feet and inches face a more complex calculation. There are concerns today about the amount of salt and sugar people consume. Food contents are labelled by the number of grams of ingredient per grams of product. People who measure food in pounds and ounces can only track their salt and sugar content with extra calculation.
The dosage of the drug is usually specified in milligrams of drug per kilogram of body mass. If patients give their weight in stones and pounds, healthcare professionals have to convert to kilograms to work out the correct dosage.
Health and safety regulations in the workplace are metric. Yet both the Government and the news media usually communicate with the public using imperial. Notice that there is a zero 0 before to the left of the decimal point.
When writing decimal numbers that are smaller than 1 in the metric system, it is customary to place a zero to the left of the decimal point. The prefixes are d, which means 0. Insert the values of the prefixes into the conversion. Skip to content Trade Math.
Convert Since the metric system is based on multiples of ten, conversions involve multiplying by multiples of ten. In Decimal Operations, we learned how to simplify these calculations by just moving the decimal.
To multiply by [latex]0. We can apply this pattern when we make measurement conversions in the metric system. Solution 1. We will convert liters to kiloliters. We will convert liters to milliliters.
Performing arithmetic operations on measurements with mixed units of measures in the metric system requires the same care we used in the U.
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