Science 3010
The Scientific Toolbox
How do scientists see bacteria? How do they measure the distance to the moon?
To build a house, a carpenter needs a hammer and a saw. To fix a car, a mechanic needs a wrench and a screwdriver. Having the right tool for the right job makes work easier. Like any other worker, a scientist needs tools as well. The exact tool he or she uses depends on what needs to be known.
Measuring is one of the most common scientific tasks. Whether it’s time, weight, temperature, or length, every measurement needs to be accurate. If a measurement hasn’t been made carefully, the result can’t be trusted, and neither can the experiment.
Scientists use the metric system for their measurements. Rulers, used to check length, have marks on them showing centimeters and millimeters. Measurements longer than a meter are often made using a measuring tape. The tape is several meters long. Because it is thin and flexible, it can be rolled up and stored in a small case.
The longest measurements are made using lasers. The amount of time the laser beam needs to hit an object and reflect back shows the distance.
Thermometers help scientists find temperature—the amount of heat something has. Scientific thermometers use the Celsius scale. For many years, thermometers were filled with mercury. It rose or fell inside them based on the amount of heat. Today, most thermometers are electronic. Mercury is a poison, and electricity is safer. It is also much more accurate.
Often what a scientist needs to study is too small or far away to be seen without help. Microscopes and telescopes are tools that magnify things. For both devices, lenses are placed inside tubes. Looking through the tubes makes objects easier to see.
Microscopes let scientists peer into the tiny worlds of bacteria and viruses. Telescopes allow them to watch what is happening in space billions and billions of miles from Earth.
科學家如何用顯微鏡觀察細菌?如何用望遠鏡觀察月亮?
就如其他行業的人一般，科學家也需要工具
而精準的儀器能夠提供這人需要知道的資訊
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