ACTIVATOR In your opinion, which would be easier to convert? Explain why. A. Meters to millimeters B. Centimeters to inches C. Inches to feet
ACTIVATOR: KWL CHART— DIMENSIONAL ANALYSIS (UNIT CANCELLATION) WHAT DO YOU KNOW ABOUT DIMENSIONAL ANALYSIS WHAT YOU WANT TO KNOW ABOUT DIMENSIONAL ANALYSIS WHAT HAVE YOU LEARNED ABOUT DIMENSIONAL ANALYSIS
DIMENSIONAL ANALYSIS AKA unit analysis or unit cancellation Involves converting one unit to a different unit by using conversion factors A. Metric to English B. English to Metric C. English to English
STEPS: 1. Write down your “given”. 2. Using conversion factors (off small sheet), make sure a top and bottom DIAGONAL unit cancel out. 3. Make sure at the end of your setup that you end up on TOP with the unit you want your answer in. 4. Multiply all the way across on top then on bottom. Divide the top /bottom. 5. The “given” determines sig figs for your answer.
Ex: 1 How far in cm is 3.50 miles? EXAMPLES Ex: 1 How far in cm is 3.50 miles?
Ex: 2 20 grams = ______________pounds
Ex: 3 How many years are in 365, 300 sec?
Ex: 4 Convert 20,005 leagues under the sea into meters
LAB—UNIT CONVERSION 1. __________________cm = ____________miles 2. _________________g = ______________tons 3. 250 mL= _______________________gallons 4. _________degrees Celsius= _________Kelvin 5. ________________seconds =__________years 6. length = __________cm= _________meters width = __________cm= ___________meters Area = ____________m 2
TEST REVIEW SHEET 1. 2,000,000 sec 14. 0.21486 mile 2. 0.85422 lb 15. 0.0128709 yr 3. 5 m 16. 0.8 gal OR 0.7 gal 5. 6.5 g/mL 17. 323 cm 6. 20. grams 18. 150 in 7. 4.9 mL 19. 0.46 m 8. 3 mL 20. 0.00954424 yr 9. 3 g/mL 24. 44.32 dam 10. 3000 g 11. 700 L 12. 100 grams 13. 5 g/mL
WARM UP-- 1. Convert 25 pounds into grams. 2. Convert 3.44 years into minutes. 3. Convert 400 mm into miles.
B) Single & Double Unit Given within the Same Problem ***must START off the problem with the SINGLE unit given FIRST ***SOMEWHERE later in the problem, the double unit given will be used like a conversion factor Ex: 1 A worm can travel slowly at a speed of 2.0 cm/sec. How many seconds will it take to travel 7.92 miles?
Ex: 2 How many minutes will it take a car moving 22 ft/sec to travel 75 meters?
Ex: 3 You fill up your car's tank with 30 L of gas. If your car gets 22 miles/gallon, how many km can you drive your car?
ACTIVATOR-- DEAR ABSENT STUDENT LETTER: Write a short letter explaining to a student who has been absent how to solve a dimensional analysis problem.