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International System of Units (SI)

scientists use this metric based system

meter

The basic SI unit of length

liter

Basic unit of volume in the metric system

weight

the force exerted by a mass as a result of gravity

kilogram

1000 grams

gram

a metric unit of weight

temperature

a measure of how hot or cold something is

Celsius

a temperature scale that defines the freezing point of water as 0 degrees and the boiling point of water as 100 degrees

Kelvin

SI unit of temperature; indicates number of units above absolute zero. To go from Celsius to Kelvin add 273. To go from Kelvin to Celsius subtract 273.

absolute zero

The coldest temperature, 0 Kelvin, that can be reached. It is the hypothetical temperature at which all molecular motion stops.

energy

the ability to do work

joule

si unit of energy

calorie

unit of heat defined as the quantity of heat required to raise the temperature of 1 gram of water by 1 degree centigrade at atmospheric pressure

Density

mass/volume

Conversion factor

a ratio derived from the equality between two different units that can be used to convert from one unit to the other