The International System of Units The international system of units also known as SI Developed in the late 1700’s This is the system of measurement used by scientists around the world.
The International System of Units The system was created to let scientists communicate even if they didn’t speak the same language. There are many different units of measurement used throughout the world.
Notes: SI system SIlets scientists all over the world use the same measurements even if they speak different languages.
SI Many of these units were based on parts of the body such as the foot. Other units such as inches were based on grains of barley. These different units caused problems when scientists from different countries tried to work together. Other problems occurred with units based on things that could change size like a foot.
About SI SI is a base 10 system This means that each unit of measurement is based on multiples of 10. This makes conversion between units easy It also eliminates fractions like in American standard, and uses decimals instead.
Notes: SI Units of Measurement The SI unit of length is meters The SI unit of mass is kilograms The SI unit of volume is liters The SI unit of temperature is Kelvin or Celsius
SI Units of Measurement SI units for length Meter (m) Kilometer (km) 1km = 1,000m Decimeter (dm) 1dm = 0.1m Centimeter (cm) 1cm = 0.01m Millimeter (mm) 1mm = 0.001m 1
SI Units of Measurement SI unit of volume Cubic meter (m³) cubic centimeter (cm³) Liter (L) Milliliter (mL)
SI units of measurement SI unit of temperature Kelvin(K) 0°C = 273K Celsius (°C ) 100 °C =373K
SI unit of Mass Kilogram (kg)- equal to 1,000 grams. Gram (g)- basic unit of mass Milligram(mg)- one thousandth of a gram,
Temperature Temperature, measures the average heat, or energy of motion, in the molecules of an object. The SI units of measure for temperature is Celsius (C) and Kelvin (K) The standard unit is Fahrenheit
Temperature Thefreezing and boiling points of water are the benchmarks for Celsius and Fahrenheit . Freezing for C is 0° and boiling temperature is 100°. This is why the Celsius scale is also known as the Centigrade scale.
Temperature Kelvin uses a different benchmark. Thelowest temperature on the Kelvin scale is absolute zero. This is the point at which all motion in molecules stop.
Common uses of SI Area: is the size of the surface of an object. You find it by multiplying length x width l xw Mass, is the amount of matter in an object. You find it by using scales. Volume, is the amount of space an object takes up, it is 3 dimensional. You find it by multiplying length x width x height, (l x w x h)
Density Density, is the amount of matter in an object in a given volume. Density = mass divided by volume or D= m v