Dimensional Analysis

NEVER use inches in science Each small Space betweendivision is millimeters large numbers(or mm) is centimeters

(or cm)

NEVER write a measurement in a fraction form!

6 ½ mm 6.5 mm

Dimensional Analysis

• Dimensional analysis- finding the proper units to measure in

• Science measures in the metric system!

• Meters measure _______________• Liters measure_________________• Grams measure________________

Base Units

ExamplesNano: 1/1,000,000,000 Nano Technology

(1 billionth)Micro: 1/1,000,000 Compound Microscopes

(1 millionth)Milli: 1/1,000 Small divisions on ruler

(1 thousandth)Centi: 1/100 Large divisions on ruler

(1 hundredth)Deci: 1/10 Measure watch size

(1 tenth)

UNIT (meters, liters, grams)Deca: 10 Measure rooms

(ten)Hecto: 100 Measure plots of land

(hundred)Kilo: 1,000 Long drivable distances

(thousand)Mega: 1,000,000 Larger than the circumference

(million) of the earthGiga: 1,000,000,000 Larger than the circumference

(billion) of earth

Size

Prefixes go BEFORE the unit

Challenge!

What unit would 1,000 grams be measured in?

1 ________________________

What unit would 10,000 liters be measured in?

1 ___________________________

What unit would 1/100,000 meters be measured in?

1 _____________________________

Conversions

giga mega kilo hecto deca Unit deci centi milli micro nanoG M k h da d c m µ n

9 8 7 6 5 4 3 2 1 1 2 3 4 5 6 7 8 9

As units get BIGGER, movethe decimal point to the LEFT

As units get SMALLER, move the decimal point to the RIGHT

Examples: 1000 mg = _____ g 1 L = __________ mL

Step 1: Determine if move decimal point left or rightStep 2: Determine how many spaces move the decimal point

English to Metric Conversions

1. Find units in conversion table similar to in the problem & write the conversion

2. Cross multiply fractions1. 1st fraction: Left side of

original equation in numerator, right side (x) in denominator

2. 2nd fraction: Set up so units are diagonal from original fraction

3. Multiply when in numerator, divide when in denominator

• 50 gallons = ________ mL

Conversion Table1 inch = 2.54 cm 1 gallon = 3.79 L1 oz = 29.57 mL 1 yard = 0.91 m1 lb = 0.45 kg 1 ft = 0.30 m1 oz = 28.35 g

You Try!

• 20 oz = ____________ kg

Challenge: Convert Among Different Types of Units (Apples to Oranges)

• You will be given a conversion example

• Set up fractions so that the units cancel out

• Multiply!

• Example:12 gallons = ______ miles(25 miles per gallon)