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# What is the difference between fundamental and derived quantities?

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### Quick Answer

**The metric system (SI) defines seven fundamental quantities that cannot be further broken down, from which all other derived quantities come.** The meter is the fundamental quantity for length. Area uses the derived quantity of square meters and volume uses cubic meters.

When measuring very small or very large units, use of the fundamental unit often becomes cumbersome. Measuring the width of a human hair using the meter requires a decimal point and several zeros. The SI system handles this prefixes that describe multiplying the base unit by a power of ten. Measuring the hair in nanometers (0.000000001 meter) is more appropriate.

Units such as the day, hour and astronomical unit, are not officially a part of the metric system, but they are often used in science. These units are also possible to derive from the SI fundamental quantities. For example, a day is 86,400 seconds, according to HowStuffWorks.

Some derived units have special names. For example, the metric system also uses the liter to measure volume. One liter is 1000 cubic centimeters. The Newton, for measuring force, is the product of acceleration (meters per second squared) and mass (kilogram) or kilogram meter per second squared. Many of the special names given to the derived units honor the work of scientists in the area the unit represents.

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Q:
## What is air density?

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Full Answer >**Air density is the mass of air per unit of volume it occupies, and it is expressed in kilograms per cubic meter when using the metric system.**In the free atmosphere, air density decreases when temperature increases or when the air is humid. However, air density increases when pressure increases.Filed Under: -
Q:
## What is 500 grams?

A:A gram is a unit of measurement for mass or weight in the metric system. There are 1000 grams in a kilogram, so 500 grams would be a half a kilogram. In US customary units, 500 grams is a little more than a pound.

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## Is the basic unit of volume in the metric system the gram?

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Full Answer >**The basic unit of volume in the metric system is the liter.**Volume is a three-dimensional measurement of space, determined by multiplying the lengths of the three dimensions occupied by matter. Therefore, cubic-meters can also be used as a unit of volume. One cubic-meter is equivalent to 1,000 liters.Filed Under: -
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## What is a millibar?

A:A millibar is part of the metric system and is a unit of pressure. It is abbreviated by mbar or mb and is derived from the bar.

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