Dimensional Analysis Converting units from one unit to another

Introduction  the skill of converting from one unit to another is called dimensional analysis.

Introduction  involves three factors: a. the unit in the given problem b. the unit the answer should be in c. the conversion factor

A conversion factor is…. 1) a fraction that always equals 1 ex. 1 kilogram equals 1000 grams 1 kg / 1000 g = 1 OR 1000 g / 1 kg = 1

B. How to do a conversion – metric to metric  Read the given problem. Determine the units you are converting to (what units your answer should be in). a. Convert 2500 g to kilograms.

How to do a conversion – metric to metric  Choose a conversion factor that includes both the unit given in the problem and the unit you need to convert to. You could choose: 1 kg / 1000 g = 1 OR 1000 g / 1 kg = 1

How to do a conversion – metric to metric  Choose the conversion factor that will allow you to cross – cancel out the units that you DO NOT want in the answer. (hint: put the units you want for the answer in the numerator position!) 2500 grams x 1 kilogram 1000 grams 1000 grams

How to do a conversion – metric to metric  Cancel out the like units (numerator/denominator).  Do the math. Multiply the fractions - reduce to its simplest form.  2500 grams x 1 kilogram = 2500kilograms 1000 grams 1000

How to do a conversion – metric to metric  2500 kilograms = 2.5 kilograms 1000 Answer = 2.5 kilograms

6 Step Method 1. Read to find the given 2. Set up the problem 3. Find the conversion factor 4. Multiply and divide 5. Record answer 6. Check work

. How to do a conversion – metric /english  Read the given problem. Determine the units you are converting to (what units your answer should be in). a. Convert 750 miles to kilometers.

How to do a conversion – metric /english  Choose a conversion factor that includes both the unit given in the problem and the unit you need to convert to. You could choose: 1 mile / kilometers = 1 OR kilometers / 1 mile = 1

How to do a conversion – metric /english  Choose the conversion factor that will allow you to cross – cancel out the units that you DO NOT WANT in the answer. (hint: put the units you want for the answer in the numerator position!) 750 miles x kilometers 1 mile 1 mile

How to do a conversion – metric /english  Cancel out the like units (numerator/denominator). 750 miles x kilometers 1 mile 1 mile

How to do a conversion – metric /english  Do the math. Multiply the fractions - reduce to its simplest form. 750 miles x kilometers 1 mile 1 mile  kilometers = kilometers 1

How to do a conversion – metric /english Answer: kilometers

Dimensional Analysis – Multistep Conversions  Example:If Gavin is running with football 30ft/second, how fast is that in meters per second?  Example: If Katelyn is a Mercedes traveling 15 mph, how fast is that in ft/sec?