Definition of Measurement

Measuring is an important scientific skill.  To measure the length of a table using a book, you compare the length of the table with the length of the book, and the book is used as a unit. Length is one of base quantity.

The result of measurement is useful if it uses a standard of measurement. It is an agreed unit of measurement with fixed value. A book used as a unit of measurement is not standard because there are different sizes of books.

Measuring systems. People used to use their body as units of measurement such as fathoms, span, foot, and step. But those units are not standard and can cause difficulty in communicating them.

You may hear people use units of measurement such as: gallon for water, yard for thread, and inch for pipe. Those units are examples of units in the British system.  After the 1700 some scientists used measuring system called the metric system. Then, in 1960 the metric system was used and officially called the international system or SI units (Le Systeme International d'Unites). In the SI, each base quantity has a unit, for example, meter for length, second for time, and kilogram for mass.

Questions:

1. Books are not standard measurement. Why?
2. What parts of body did people use to use as units of measurement?
3. What is a unit for ‘time’?
4. What is a unit for ‘mass’?
5. “Those units are examples of units in the British system.” What does the underlined word refer to?
6. What measuring system did scientist use after the 17^th century?

Written by TamaGuci

We are Creative Blogger Theme Wavers which provides user friendly, effective and easy to use themes. Each support has free and providing HD support screen casting.