Since children are used to compare quantities, a process that basically called measure. When we started this process, we make mistakes in association with the object being compared and not the units we use, so for example, no wonder the error in the rapid response to the question, what weighs more, a kilogram of feathers or one kg of iron?
The measurement is the determination of the ratio between the size of an object or event and a particular unit of measurement is to compare the unknown quantity that we identify and a known quantity, we choose as a unit.
certainly has been a necessity measure of humanity through history, man long used anthropometric units, ie as a unit of measurement, body parts: the inch, foot, the Jerne, fourth, elbow, among others. All these units are arbitrary, for each foot or inch vary in size depending on the individual. Little by little they overcome these difficulties by, as units of measure, quantities that were fixed and did not change with time. There appears meters, however, and interestingly, its initial definition given by the French Academy of Sciences in 1791 as "the ten-millionth of the distance from the center of the line of Ecuador Land" has changed several times since then (in the year 1960, a meter is equal to 1,650,763.73 wavelengths of orange-red light emitted by the atom of krypton-86, and in the year 1983 as the length traveled by light in vacuum in 1 / 299,792,458 seconds) .
important in this process is the unit of measurement used, however, does not want to lose their interest in these first lines, so I will not go into details of the systems measures rather my interest is to share some concerns on this issue, specifically on the unconventional units.
For example, the height of my body is close to 1.70 meters, or put another way, 1 meter and 70 cm, clear that if I use the foot as the unit of measure, as is customary in some countries would say that my height is close to 5.5 feet. Of course, according to what we wrote at the beginning of this entry, we must know what equals one meter or one foot for comparison. We measured
mass in kilograms (kg) is common to use the Celsius scale (or Centigrade), and in the Anglo-Saxon countries , scale Fahrenheit to measure temperature , the time is measured in years, minutes or seconds, the force in Newtons, the wage in colones, dollars or euros.
But think of when you go to buy a pair of shoes or eyeglasses, what unit uses? In the shoe store asking for a 9 or maybe a 10, will be a 43 or 44. In the view tell us that our ranking is 3 but 3 What?
Well, let's begin with a quick refresher on diopter, which is the securities unit expressing positive or negative refractive power of a lens, and is equivalent to the reciprocal or inverse of focal length in meters. The sign '+' (positive) corresponds to the convergent lenses, which correct farsightedness , and '-' (negative) to the divergent, which correct nearsightedness . Thus, a lens whose focal length +1 is the metro, have a power of 1 diopter and a +2 diopter lens is a converging lens of focal length of ½ meter.
Now to the extent of footwear, from the eighteenth century, used his own unit: point. Of course, before the adoption of the metric system, different regions had their own measure to the point, so we can talk about Paris, Berlin or the point about Vienna that they had agreed local shoemakers. The differences by region little impact until the late nineteenth century when the Industrial Revolution production changed forever and implemented the systems of mass production, where production of large amounts decreased costs. It is precisely in the early nineteenth century, thanks to the expansion of Napoleonic Empire, stretching across Europe about the use of Paris. This point is equal to 2 / 3 cm, ie 6.667 mm, with 3 points or numbers that are equivalent to 2 cm.
other hand, recall that in the early fourteenth century, Edward II, King of England, ordered three grains of barley, online, forming a inch (2.54 cm) and 12 inches formed a standing (30.48 cm), so the shoemaker shoes taken as unit equivalent to a grain of barley, ie 1 / 3 inch or 8.467 mm. Thus, the "size" 1 \u200b\u200bequals to 22 cm, or whatever it is, about 33 French.
To improve the measurement and greater precision, many countries introduced measures or points average, 3.334 mm 4.234 mm in France or in England. Moreover, in U.S. follow the English model but varies the starting point, because the scale starts before 1.116 mm, which means that compared to the English system, each number begins a little earlier, so, 11 in USA is equivalent to 10.5 in the UK (United Kingdom).
will conclude with a reminder of my youth and in fact is what motivates this entry. In the company of my brother, a passion for progressive music, often listened to the fantastic album Albedo 0.39 "by Vangelis a name and it seemed surreal. Well, today I know, and wanted to share with you the Albedo is the ratio between the intensity of the reflected light and the incident by a celestial body that does not emit light itself. Is measured with a number between 0 and 1, after establishing that 0 is the albedo of a body that reflects no light and 1 as the albedo of a body that reflects all the incident light. For example, 0.4 is the albedo of a celestial object that reflects 40% of the incoming light. The higher albedo planet in our solar system is Venus with 0.65, then Jupiter is with 0.52 and third Neptune, with 0.41. The Earth has an albedo of 0.39. The albedo of the Moon is, 08 or 8%, ie at night when we look at the moon, we are only seeing 8% of energy gives total sun dark surfaces absorb more energy and light surfaces like snow, reflect it.
Finally, the albedo is a measurement for monitoring of climate change on Earth and this enhances its importance today.
certainly has been a necessity measure of humanity through history, man long used anthropometric units, ie as a unit of measurement, body parts: the inch, foot, the Jerne, fourth, elbow, among others. All these units are arbitrary, for each foot or inch vary in size depending on the individual. Little by little they overcome these difficulties by, as units of measure, quantities that were fixed and did not change with time. There appears meters, however, and interestingly, its initial definition given by the French Academy of Sciences in 1791 as "the ten-millionth of the distance from the center of the line of Ecuador Land" has changed several times since then (in the year 1960, a meter is equal to 1,650,763.73 wavelengths of orange-red light emitted by the atom of krypton-86, and in the year 1983 as the length traveled by light in vacuum in 1 / 299,792,458 seconds) .
important in this process is the unit of measurement used, however, does not want to lose their interest in these first lines, so I will not go into details of the systems measures rather my interest is to share some concerns on this issue, specifically on the unconventional units.
For example, the height of my body is close to 1.70 meters, or put another way, 1 meter and 70 cm, clear that if I use the foot as the unit of measure, as is customary in some countries would say that my height is close to 5.5 feet. Of course, according to what we wrote at the beginning of this entry, we must know what equals one meter or one foot for comparison. We measured
mass in kilograms (kg) is common to use the Celsius scale (or Centigrade), and in the Anglo-Saxon countries , scale Fahrenheit to measure temperature , the time is measured in years, minutes or seconds, the force in Newtons, the wage in colones, dollars or euros.
But think of when you go to buy a pair of shoes or eyeglasses, what unit uses? In the shoe store asking for a 9 or maybe a 10, will be a 43 or 44. In the view tell us that our ranking is 3 but 3 What?
Well, let's begin with a quick refresher on diopter, which is the securities unit expressing positive or negative refractive power of a lens, and is equivalent to the reciprocal or inverse of focal length in meters. The sign '+' (positive) corresponds to the convergent lenses, which correct farsightedness , and '-' (negative) to the divergent, which correct nearsightedness . Thus, a lens whose focal length +1 is the metro, have a power of 1 diopter and a +2 diopter lens is a converging lens of focal length of ½ meter.
Now to the extent of footwear, from the eighteenth century, used his own unit: point. Of course, before the adoption of the metric system, different regions had their own measure to the point, so we can talk about Paris, Berlin or the point about Vienna that they had agreed local shoemakers. The differences by region little impact until the late nineteenth century when the Industrial Revolution production changed forever and implemented the systems of mass production, where production of large amounts decreased costs. It is precisely in the early nineteenth century, thanks to the expansion of Napoleonic Empire, stretching across Europe about the use of Paris. This point is equal to 2 / 3 cm, ie 6.667 mm, with 3 points or numbers that are equivalent to 2 cm.
other hand, recall that in the early fourteenth century, Edward II, King of England, ordered three grains of barley, online, forming a inch (2.54 cm) and 12 inches formed a standing (30.48 cm), so the shoemaker shoes taken as unit equivalent to a grain of barley, ie 1 / 3 inch or 8.467 mm. Thus, the "size" 1 \u200b\u200bequals to 22 cm, or whatever it is, about 33 French.
To improve the measurement and greater precision, many countries introduced measures or points average, 3.334 mm 4.234 mm in France or in England. Moreover, in U.S. follow the English model but varies the starting point, because the scale starts before 1.116 mm, which means that compared to the English system, each number begins a little earlier, so, 11 in USA is equivalent to 10.5 in the UK (United Kingdom).
will conclude with a reminder of my youth and in fact is what motivates this entry. In the company of my brother, a passion for progressive music, often listened to the fantastic album Albedo 0.39 "by Vangelis a name and it seemed surreal. Well, today I know, and wanted to share with you the Albedo is the ratio between the intensity of the reflected light and the incident by a celestial body that does not emit light itself. Is measured with a number between 0 and 1, after establishing that 0 is the albedo of a body that reflects no light and 1 as the albedo of a body that reflects all the incident light. For example, 0.4 is the albedo of a celestial object that reflects 40% of the incoming light. The higher albedo planet in our solar system is Venus with 0.65, then Jupiter is with 0.52 and third Neptune, with 0.41. The Earth has an albedo of 0.39. The albedo of the Moon is, 08 or 8%, ie at night when we look at the moon, we are only seeing 8% of energy gives total sun dark surfaces absorb more energy and light surfaces like snow, reflect it.
Finally, the albedo is a measurement for monitoring of climate change on Earth and this enhances its importance today.
"By the same token that measure will be measured"
San Mateo 7: 2
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