PICK UP 1. Paper(s) 2. Sign in for attendance 3. CALCULATOR! TURN IN Any late HW!

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1 PICK UP 1. Paper(s) 2. Sign in for attendance 3. CALCULATOR! TURN IN Any late HW! DO NOW 1. On a half sheet of paper rearrange this equation to solve for vi a = v f v i t HW: U0 6 (Wed) Next Test: U0 Test Mon, 9/10

2 By the end of today, IWBAT -effectively use dimensional analysis to convert between units. Why it matters in LIFE: Part of being a functional human being is being able to understand what s happening in the world around you! Why it matters in THIS CLASS: Our Goal = 80% Mastering today s lesson (focused participation, asking questions, etc) is the first brick that will help us reach our goal for this unit, and eventually for the year

3 TEKS: By the end of today, IWBAT -effectively use dimensional analysis to convert between units. Topic: Units & Dimensional Analysis

4 HOW MANY MS. KELLY S TO THE MOON?

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6 UNITS Base Units basic units that make up the rest Length Meter, m Time Seconds, s Mass Kilogram, kg Derived Units units made up of a combination of base units Force Newton, N Energy Joule, J Etc.

7 WHAT IS DIMENSIONAL ANALYSIS? Dimensional Analysis is the problem solving method we will use to convert between units For example: Time can be measured in seconds, minutes, or hours You CAN convert seconds minutes hours You CANNOT convert seconds centimeters

8 UNIT CONVERSIONS Equivalence Statement: Two measurements with the exact same value Example: 1 ft = 12 in See a list on the handout! Conversion Factor: ratio of the two parts of an equivalence statement Example 1 ft OR 12 in 12 in 1 ft

9 UNIT CONVERSIONS To change from one unit to another we will use a conversion factor: given unit desired unit given unit = desired unit Quick example: 14cm =? m

10 G Given information and variables What do you know? What can you pull from the problem? U Unknown information and variables What do you need to know? What is the problem looking for? E Equations What equations do you have that include the given and unknown information/variables? S Substitute Substitute the given information/variables into the equations S Solve/Sentence Solve for the unknown information/variables and write your answer in context in a sentence. DON T GUESS, G.U.E.S.S.!

11 EXAMPLE #1 G. Identify your given. Circle it in the problem and write it down. U. Identify your unknown. Box it in the problem and write it down. The length of one lab desk is 38 inches. What is the length in centimeters?

12 EXAMPLE #1 E. Find the equivalence statement that relates the two units.

13 EXAMPLE #1 S. Choose the correct conversion factor based on your given and unknown. 1 in/2.54 cm OR 2.54 cm/1 in

14 EXAMPLE #1 S. Multiply your given by your conversion factor and cross off the units that cancel! 38 in 2.54 cm = desk 1 in cm desk Each desk is cm long!

15 GP #1 W/ YOUR TABLE PARTNER A snail moves at 0.03 miles per hour. How fast is it moving in meters/second?

16 GP #1 W/ YOUR TABLE PARTNER A snail moves at 0.03 miles per hour. How fast is it moving in meters/second? G: 0.03 mi/hr U: m/s? E: 1 mi = 1609m, 1 hr = 60 min, 1 min = 60s S: 0.03 mi/hr * 1609 m/1mi * 1hr/60 min * 1min/60sec =? S: The snail is moving at meters per second.

17 HOW MANY MS. KELLY S TO THE MOON?

18 INDEPENDENT PRACTICE! Procedure for IP time: 1) Silent work time 2) Try and solve without notes first! Hierarchy of who to ask 1) Your brain 2) Your notes 3) Your partner (quiet whisper) 4) Ms. Kelly

19 EXIT TICKET On a half sheet of paper: 1. A cheetah travels at 64 miles/hour. Determine how fast it is moving in meters/second. HW: U0 6 (Wed) Next Test: U0 Test Mon, 9/10

20 EXIT TICKET On a half sheet of paper: 1. A cheetah travels at 64 miles/hour. Determine how fast it is moving in meters/second. The cheetah is moving at m/s. Turn in to exit ticket slot of the filer for your class period. HW: U0 6 (Wed) Next Test: U0 Test Mon, 9/10