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## Measuring Length

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**Measuring Length**Done by: Graeme Smit, Muhammad AbbasQasim, Yazdi and Payman**Introduction**This is a brief overview of the history of measuring length and how it is being used, outlining some of the more important and interestingaspects.**Measurement has been importantever since man settled from**his nomadic lifestyle and started using building materials; occupying land and trading with his neighbors. As society has become more technologically orientated much higher accuracies of measurement are required in an increasingly diverse set of fields, from micro-electronics to interplanetary ranging.**Si Units**• The unit for measuring length globally recognized is: • Meters=m**History of measuring length**Units of measurement were among the earliest tools invented by humans. Our present knowledge of early weights and measures comes from many sources. One of the oldest units of length measurement used in the ancient world was the 'cubit' which was the length of the arm from the tip of the finger to the elbow. This could then be subdivided into shorter units like the foot, hand (which at 4 inches is still used today for expressing the height of horses) or finger, or added together to make longer units like the stride. The cubit could vary considerably due to the different sizes of people. The cubit(finger tip to elbow)**Modern day unites of length**• In this part of the world the Metric system is used. • 1 millimeter = 0.001 meter • 1 centimeter = 0.01 meter • 1 decimeter = 0.1 meter • 1 kilometer = 1000 meters • For reference, 1 meter is a little longer than 1 yard or 3 feet. It is about half the height of a very tall adult. A centimeter is nearly the diameter of a dime, a little less than half an inch. A millimeter is about the thickness of a dime.**Instruments for measuring length**• Vernier caliper • Micrometer • Ruler • Tape measure**Things possible with length.**Using length we can even find the area. It is a simple formula called lxb. Length x width. For example we measured the length and width of our school, these were the measurements we got. Length=170metres Width = 70 metres Using the information and the formula above can you calculate the area of your school?**Fun facts!**• The end of your thumb to your first joint is about 1inch long. • An egg carton is about a footlong. • Distancesbetween cities are measured in kilometer.