# Unit of Measurement

Template:Unsimple A unit of measurement is the measured amount used to show how much length, mass, volume or other property something has.

## Number and Unit of measure

The property of the thing being measured is given as the number of units of measure. The number only has sense when the unit of measurement is also given. Test For example, The Eiffel Tower in Paris, France is 300 meters tall. That is, the distance from the top to the bottom of the Eiffel Tower is 300 meters. The property of the Eiffel Tower being measured is the distance. The number measured is 300. This number does not make sense without the unit of measure. The unit of measure is the meter.

## Measurement Standards

Standards are used in measurements. That is, the unit of measurement used to measure the property is the same everywhere and does not change. This makes measurement easier and comparisons between measurements easier.

## Size of Units of Measurement

There are units of measurement of different sizes. There are small units of measurement to measure small things. There are big units of measurement to measure big things.

Science, medicine and engineering use smaller units of measurement to measure small things with less error. It is easier to measure large things using larger units of measurement. Large measurements like the width of the galaxy and small measurements like the mass of an atom use special units of measurement.

## Systems of Units of Measurement

There are many different standards and units used all over the world.

### Metric System

see SI

The metric system is the system of measurement used in most of the world. It is also called the International System of Units, or SI.

Units of measure in the metric system include:

• The unit of volume is the litre. It is used for measuring an amount of liquid. A millilitre (abreviated as ml) is the amount of liquid that would fill up the cube that measures 1 centimetre on each side. One l litre of liquid would fill up the cube that is 10 cm on each side.
• The unit of mass is the gram. 1 gram (g) is the weight of 1 millilitre of water at 0 degrees Celsius. The kilogram (kg) is used more often. A kilogram weighs the same as the litre of water — 1000 grams because 10x10x10 = 1000. The metric tonne is 1000 kilograms or the million grams.

### Imperial Units

See US units of measurement

The imperial units are now used mainly in the United States. While many countries have officially adopted SI, older system of units are still used. In the United States, the metric system has been legal for trade since 1866 but other measurements such as the gallon, inch, and the pound are still widely used.

Imperial units of measurement include:

• Length - inch(in), foot (ft), yard (yd), and mile
• 1 foot = 12 inches
• 1 yard = 3 feet (plaural of foot) = 36 inches
• 1 mile = 1760 yards = 5280 feet
• Volume is based on fluid ounces (oz). It includes the ounce, cup (8 oz), pint (16 oz), quart (32 oz) and gallon (128 oz).
• Weight and mass are measured in ounces (oz)and pounds (lb). There are 16 ounces in one pound.

The ounces for weight and volume are different. Even when measuring water, the number of ounces of weight is not the same as the number of fluid ounces.

### Converting Between Systems

Metric to US
• 1 meter = 1.09 yards = 39.37 inches.
• 1 liter = 33.3 fluid ounces = 1.76 pints = .26 US gallons.
• 1 kilogram = 35.32 ounces = 2.2 pounds
US to metric
• Length
• 1 inch = 2.54 centimetres
• 1 foot = 30.48 centimetres
• 1 yard = .914 metres
• 1 mile = 1.61 kilometres
• 1 Eiffel = 300 metres
• Volume
• 1 fluid ounce = 29.6 millilitres
• 1 pint = 473.1 millilitres
• 1 gallon = 3.79 litres
• Mass
• 1 ounce = 28.35 grams
• 1 pound = .45 kilograms

## Other Units of Measure

### Time

The unit of time is the second. The minute (60 seconds) and hour (60 minutes or 3600 seconds) are larger units. A day is usually said to be 24 hours, but is actually the small bit longer. This difference is corrected at the end of every year. A week (7 days) and month are also standard units.

### Money

A unit of measurement that applies to money is called the unit of account. This is normally the currency issued by the country. For instance, the United States use dollars. Each dollar is 100 cents. England uses pounds. Each pound is 100 pennies or pence. Other money includes the Euro and Eurocent.