閱讀筆記 S3012 The Metric System

Science 3012
The Metric System
Why has the metric system become the scientific standard for measurement? 
If someone asks how tall you are, you’ll probably answer in feet and inches. If you were a scientist, though, you’d most likely answer in meters.
 The metric system was created in France during the 1700s. Scientists wanted a simpler way to compare things. The old way was complicated.  For example one gallon of water weighs 8.33 pounds. If you want to know the weight of 14 gallons of water, the math is not simple.
French King Louis XIV asked his scientists to invent an easier system. Their answer was the metric system. All of its measurements are based on the number ten and a length called the meter.
 The oldest measurements began as body parts. This is where the term foot comes from. The French scientists wanted their new system to be based on something more precise. They decided the meter would be a small fraction of the distance between Earth’s two poles.
For many years, an official meter stick was kept in France. All other meters were based on it.  Soon, scientists tired of having to rely on this one meter. They wanted to be able to find the exact length without having to travel to France. Today, one meter is defined as the distance light travels in1/299,792,458 of a second. Now, that’s accurate!
 A meter is divided into one hundred centimeters. One thousand meters makes one kilometer. Conversion is much simpler when a system is based on tens — you just need to move the decimal point. For example, something that is 350 meters long is also 0.35 kilometers long or 35,000 centimeters long.
 Different types of measurements are linked with each other as well. Metric length, weight, and volume are related based on water. If you could form water into a box shape that was one centimeter on each side (length), it would be one cubic centimeter. One cubic centimeter of water equals one milliliter of water (volume), which weighs about one gram (weight).
 Because these conversions are so simple, most scientists and nations use the metric system.  


為甚麼公制的系統會變成科學家測量的標準?
當一個人問你的身高時，你可能會用英呎或英吋來表達
而如果你是一位科學家的話，你會偏好用公尺回答
公制的系統在18世紀的法國被建立出來
當時的國王路易XIV要他的科學家們創造出一個較簡單的測量系統
也因此制定了距離為10的長度叫公尺