Dimensional AnalysisDimensional Analysis
Converting units from one unit to Converting units from one unit to anotheranother
IntroductionIntroduction
the skill of converting from one unit to the skill of converting from one unit to another is called dimensional analysis.another is called dimensional analysis.
IntroductionIntroduction
involves three factors:involves three factors:
a. the unit in the given problema. the unit in the given problem
b. the unit the answer should be inb. the unit the answer should be in
c. the conversion factor c. the conversion factor
A conversion factor is….A conversion factor is….
1) a fraction that always equals 11) a fraction that always equals 1ex. 1 kilogram equals 1000 gramsex. 1 kilogram equals 1000 grams
1 kg / 1000 g = 1 1 kg / 1000 g = 1
OROR
1000 g / 1 kg = 11000 g / 1 kg = 1
B. How to do a conversion – metric to B. How to do a conversion – metric to metricmetric
Read the given problem. Determine the Read the given problem. Determine the units you are converting to (what units units you are converting to (what units your answer should be in).your answer should be in).
a. Convert 2500 g to kilograms.a. Convert 2500 g to kilograms.
How to do a conversion – metric to metricHow to do a conversion – metric to metric
Choose a conversion factor that includes Choose a conversion factor that includes both the unit given in the problem and the both the unit given in the problem and the unit you need to convert to. You could unit you need to convert to. You could choose:choose:
1 kg / 1000 g = 1 1 kg / 1000 g = 1
OROR
1000 g / 1 kg = 11000 g / 1 kg = 1
How to do a conversion – metric to metricHow to do a conversion – metric to metric
Choose the conversion factor that will Choose the conversion factor that will allow you to cross – cancel out the units allow you to cross – cancel out the units that you DO NOT want in the answer. that you DO NOT want in the answer. (hint: put the units you want for the (hint: put the units you want for the answer in the numerator position!)answer in the numerator position!)
2500 grams2500 grams x x 1 kilogram1 kilogram
1000 grams1000 grams
How to do a conversion – metric to metricHow to do a conversion – metric to metric
Cancel out the like units Cancel out the like units (numerator/denominator).(numerator/denominator).
Do the math. Multiply the fractions - Do the math. Multiply the fractions - reduce to its simplest form.reduce to its simplest form.
2500 grams x 2500 grams x 1 kilogram 1 kilogram = = 2500kilograms2500kilograms
1000 grams1000 grams 1000 1000
How to do a conversion – metric to metricHow to do a conversion – metric to metric
2500 kilograms 2500 kilograms = 2.5 kilograms = 2.5 kilograms 10001000
Answer = 2.5 kilogramsAnswer = 2.5 kilograms
6 Step Method6 Step Method
1. Read to find the given1. Read to find the given
2. Set up the problem2. Set up the problem
3. Find the conversion factor3. Find the conversion factor
4. Multiply and divide4. Multiply and divide
5. Record answer5. Record answer
6. Check work6. Check work
. . How to do a conversion – metric /englishHow to do a conversion – metric /english
Read the given problem. Determine the Read the given problem. Determine the units you are converting to (what units units you are converting to (what units your answer should be in).your answer should be in).
a. Convert 750 miles to kilometers.a. Convert 750 miles to kilometers.
How to do a conversion – metric /englishHow to do a conversion – metric /english
Choose a conversion factor that includes Choose a conversion factor that includes both the unit given in the problem and the both the unit given in the problem and the unit you need to convert to. You could unit you need to convert to. You could choose:choose:
1 mile / 1.602 kilometers = 1 1 mile / 1.602 kilometers = 1
OROR
1.602 kilometers / 1 mile = 11.602 kilometers / 1 mile = 1
How to do a conversion – metric /englishHow to do a conversion – metric /english
Choose the conversion factor that will Choose the conversion factor that will allow you to cross – cancel out the units allow you to cross – cancel out the units that you DO NOT WANT in the answer. that you DO NOT WANT in the answer. (hint: put the units you want for the (hint: put the units you want for the answer in the numerator position!)answer in the numerator position!)
750 miles x 750 miles x 1.602 kilometers1.602 kilometers
1 mile1 mile
How to do a conversion – metric /englishHow to do a conversion – metric /english
Cancel out the like units Cancel out the like units (numerator/denominator).(numerator/denominator).
750 miles x 750 miles x 1.602 kilometers1.602 kilometers
1 mile1 mile
How to do a conversion – metric /englishHow to do a conversion – metric /english
Do the math. Multiply the fractions - Do the math. Multiply the fractions - reduce to its simplest form.reduce to its simplest form.
750 miles x 750 miles x 1.602 kilometers1.602 kilometers 1 mile1 mile
1201.5 kilometers1201.5 kilometers = 1201.5 kilometers = 1201.5 kilometers1 1
How to do a conversion – metric /englishHow to do a conversion – metric /english
Answer: 1201.5 kilometers Answer: 1201.5 kilometers
Dimensional Analysis Dimensional Analysis ––Multistep ConversionsMultistep Conversions
Example:If Gavin is running with football Example:If Gavin is running with football 30ft/second, how fast is that in meters per 30ft/second, how fast is that in meters per second?second?
Example: If Katelyn is a Mercedes Example: If Katelyn is a Mercedes traveling 15 mph, how fast is that in traveling 15 mph, how fast is that in ft/sec?ft/sec?