Metric System Part 1 The Metric System Is

Metric System Part 1

The Metric System • Is a system of measurement. • Is also known as the “S. I. System”. (System International)

Metric System Quantity Unit Symbol Distance meter m Mass gram g Volume liter L Time second s Temperature degrees celsius o. C

Prefixes every student should know… Prefix Symbol Means. . Example milli- m thousandth m. L centi- c hundredth cg kilo- k thousand km

Tools of Measurement Quantity Unit (unit symbol) Tool Distance meter (m) meterstick or ruler Mass gram (g) balance Volume liter (L) graduated cylinder or beaker

WHY USE METRIC?

Benefits of the Metric System: • It uses the decimal system (10’s!) • It is an International Standard. • The units relate to each other. * *(More on this later!)

kilo, centi, milli • Be able to give your answer using any of these prefixes! For example: • A snowboard is – 1. 85 m or – 185 cm or – 1850 mm How do you do that?

Problem: How many centimeters is 1. 5 meters? There are many ways to solve this problem. One way is Common Sense: 1. The Metric System prefixes work by multiples of 10. So, the answer must be found by just moving the decimal point. Some possible answers are: 15 cm, 1500 cm, 0. 15 cm, 0. 015 cm 2. Which of these are reasonable answers?

Does the measurement make sense? – 1 cm = width of a fingernail – 1 g = mass of a push pin – 1 m. L = ~20 drops of water

Practice Guessing: 1. 5 m 12 cm = = 150 cm 0. 12 m 0. 295 m = 295 mm 0. 8 m 80 = cm

Metric System Part 2

Metric System Quantity Unit Symbol Distance meter m Mass gram g Volume liter L

kilo, centi, milli • Be able to give your answer using any of these prefixes! For example: • A snowboard is – 1. 85 m or – 185 cm or – 1850 mm How do you do that?

Practice Guessing: 1. 5 m 12 cm = = 150 cm 0. 12 m 0. 295 m = 295 mm 0. 8 m 80 = cm

Metric Staircase. k - kilo h - hecto • Move up a step (left): …decimal moves left da - deca (no prefix) -base just meter, liter, or gram • Move down a step (right): …Decimal moves right d - deci centi c - centi m - milli

Practice 1500 cm = 15 m 0. 012 m = 12 mm 29, 500 cm = 0. 295 km 0. 08 km = 8000 cm

Does the measurement make sense? – 1 cm = width of a fingernail – 1 g = mass of a push pin – 1 m. L = ~20 drops of water

Metric System Quantity Unit Symbol Distance meter m Mass gram g Volume liter L

What is mass? • Mass is a measure of the amount of a substance. • Mass is not weight • Mass is not “how much space something takes up”; (that’s what volume is!)

Mass versus Weight • Your mass is the same everywhere in the universe • Your weight is less on the moon than it is on earth, because weight depends on gravity. link

Tools of Measurement Quantity Unit (unit symbol) Tool Distance meter (m) meterstick or ruler Mass gram (g) balance Volume liter (L) graduated cylinder or beaker

Practice Prefixes, Methods of Metric Conversion • Prefixes are Universal – cg, cm, c. L, etc. • Review Methods: – Common sense – Metric Staircase • Introduce Method: – Dimensional Analysis • Practice with balances • Practice with common sense conversion and then staircase conversion using grams and kilograms, etc.