Metrics The scientific units of measurement

Why do scientists use metric units? Easy to use Based on the decimal system (each unit is 10 times larger than the next) Precise/Accurate measurements smaller than an inch so you don’t have to use fractions No memorization of conversion facts e.g. 1 mile= 5,280 feet Globally used so no conversion is needed from one country to the next

Metric measurement of mass Mass: measure of the amount of matter in an object….an object’s mass never changes! Weight: measure of the gravitational pull acting on the object…an object’s weight depends on its mass and location…On Mars a person weighs less than on Earth because the pull of gravity on Mars is weaker than on Earth. Units of mass: kilogram (kg), gram (g), milligram (mg)

Metric measure of length Meter (m) is the basic measurement of length. Metric units of length: kilometer (km), meter (m), centimeter (cm), millimeter (mm)

Metric measurement of volume Volume: how much space something occupies or takes up. Metric units of volume: liter (L), milliliter (mL)

Metric measurement of Temperature Celsius scale is used Basics: Water freezes at 0 degrees C and boils at 100 degrees C (compared to Fahrenheit scale water freezes at 32 degrees F and boils at 212 degrees F at sea level)

Guidelines to using metrics 7 basic units or stair steps Conversions…”monkey butts” King Henry Doesn’t Usually Drink Chocolate Milk. The Middle box contains the base units…left and right are prefixes that are attached to the base units (km,kg,kL…mm,mg,mL) Name Symbol Unit Kilo k 1000 Hecto h 100 Deka da 10 Meter,gram, or liter m,g, L 1 Deci d.1 Centi c.01 Milli m.001