1. Chapter 1 Dimensional Analysis (or, Converting Units)

2. Something you probably know how to do…. How many seconds are in one day?

3. Math Review All equal 1! You can think of units like numbers…

4. Converting Units  Conversion Factor: two measurements that are equal, but have different units Examples: Examples: 1 foot = 12 inches1 foot = 12 inches 100 cm = 1 meter100 cm = 1 meter 60 seconds = 1 minute60 seconds = 1 minute  Dimensional Analysis: a fancy name for “converting units”

5. Conversion Factors What is the value of the following: Conversion factors can be flipped as needed because the ratio equals 1: ?

6. Steps to Converting Units Step 1: Write down the given quantity and unit. EXAMPLE: Convert 18000 seconds to hours. Step 2: List all necessary conversion factors. ( # with unit = # with unit) Step 3: Begin writing the conversion factors as fractions multiplied together.

7. Converting Units EXAMPLE: The ninth grade class at Irondale is having a pizza reward lunch for collecting the most food in a food drive. Each student will get 2 slices of pizza. Each pizza has 12 slices. There are 450 students total in ninth grade. How many pizzas need to be ordered?