Fundamental Units of Measure
The fundamental units of measurement are used to describe pure quantities , that is, those that do not depend on others to express themselves.
- Distance: meter (m), mile (mi), inch (in), foot (ft).
- Mass: gram (g), pound (lb), ounce (oz), mole (mol).
- Time: second (s), minute (min), hour (h).
- Temperature: Celsius (° C), Fahrenheit (° F), Kelvin (K), Rankine (R).
- Luminous intensity: Candela (Cd).
- Amount of substance: Mol (mol).
- Electric charge: Coulomb (C).
These units are universal; they are already standardized and supported by the International System of Units. The fundamental units are combined with each other to refer to other more complex quantities, by means of derived units .
Derived Units of Measure
Derived units express physical quantities that depend on two or more pure quantities. The fundamental units are related to each other to create them, thus facilitating an infinity of calculations in all branches of physics, to know in greater detail how the known world behaves.
- Area: square meter (m 2 ), square inch (in 2 ), square foot (ft 2 ).
- Volume: cubic meter (m 3 ), cubic inch (in 3 ), cubic foot (ft 3 ).
- Velocity: meter per second (m / s), inches per second (in / s), feet per second (ft / s).
- Acceleration: meter per second squared (m / s 2 ), inches per second squared (in / s 2 ), feet per second squared (ft / s 2 ).
- Density: kilograms per cubic meter (kg / m 3 ), grams per cubic centimeter (g / cm 3 ), pounds per cubic foot (lb / ft 3 ).
- Electric current: Ampere (A) or coulomb per second (C / s).
- Force: Newton or kilogram-meter over second squared (kgm / s 2 ).
- Energy or work: Joule (J) or Newton-meter (Nm), or kilogram-meter squared over second squared (kgm 2 / s 2 ).
- Concentration: moles per liter (mol / L), equivalents per liter (eq / L), grams per liter (g / L).
There are two main systems of units, which have established their own ways of dealing with quantities: the International System of Units and the English System.
The International System of Units originated in the United States, and was based on irrefutable patterns that occur in nature, as in the case of the meter, unit of distance, equivalent to the distance that light travels in a vacuum in 1/299792458 second. And the kilogram, which has been standardized from a solid body of an inert, unalterable metal.
The most representative units of the international system are:
- Distance: meter (m) and its multiples centimeters (cm), kilometers (Km).
- Mass: gram (g) and its multiples milligram (mg), kilogram (Kg).
- Volume: cubic meter (m 3 ), liter (L) or cubic decimeter (dm 3 ), milliliter (mL) or cubic centimeter (cm 3 ).
The English System is a British system that had its origin in the body measurements of an ancient monarch and in arbitrary measurements that were made in everyday life.
The most representative units of the English system are:
- Distance: inch (in), foot (ft), mile.
- Mass: pound (lb), ounce (oz).
- Volume: gallon (gal), barrel (bbl).
60 examples of units of measure
30 examples of units of measurement in the International System
- Meter (m)
- Decimeter (dm)
- Centimeter (cm)
- Millimeter (mm)
- Micrometer (μm)
- Nanometer (nm)
- Picometer (pm)
- Decameter (Dm)
- Hectometer (Hm)
- Kilometer (Km)
- Milligram (mg)
- Gram (g)
- Kilogram (Kg)
- Square meter (m 2 )
- Cubic meter (m 3 )
- Meter per second (m / s)
- Kilometers per hour (Km / h)
- Meter per second squared (m / s 2 )
- Cubic meter per kilogram (m 3 / Kg)
- Kilogram per cubic meter (Kg / m 3 )
- Gram per cubic centimeter (g / cm 3 )
- Liter (L)
- Milliliter (mL)
- Coulomb (C)
- Coulomb per second (C / s)
- Candela (Cd)
- Volt (V)
- Newton (N)
- Joule (J)
- Pascal (Pa)
30 examples of units of measurement in the English system
- Inch (in)
- Foot (ft)
- Yard (yd)
- Mile (mi)
- Pound (lb)
- Furlong (fur)
- String (ch)
- Rod (rd)
- Acre (ac)
- Ounce (oz)
- Ton (ton)
- Inches per second (in / s)
- Feet per second (ft / s)
- Yards per second (yd / s)
- Miles per second (mi / s)
- Square inch (in 2 )
- Cubic Inch (in 3 )
- Square foot (ft 2 )
- Cubic foot (ft 3 )
- Pounds per square inch (lb / in 2 )
- Pounds per cubic inch (lb / in 3 )
- Pounds per square foot (lb / ft 2 )
- Pounds per cubic foot (lb / ft 3 )
- Fahrenheit (° F)
- Rankine (R)
- Gallon (gal)
- Fourth (qt)
- Moles per cubic inch (mol / in 3 )
- Moles per cubic foot (mol / ft 3 )