METRIC CONVERSION

What are Metric Conversions? Sometimes we need to change from one measurement to another. This is usually done because the unit that is used is either too big or too small for that type of measurement.

Sometimes the number is too big for the unit being measured. 525,568 millimeters Sometimes the number is too big for the unit being measured.

Sometimes the number is too small for the unit being measured .00654 km Sometimes the number is too small for the unit being measured

How Do We Fix This Problem? We can correct these problems by doing a process called Metric Conversion. When you do a Metric Conversion, you are changing from one unit of measurement to another.

So How Do I Do A Metric Conversion? We will be using 2 methods: 1) The Stair-step Method of Metric Conversion. It requires two things; one, that you be able to count to 6, and two, that you know your left from your right. 2) The “Conversion Cross” uses fractional equivalencies for conversions

The Stair-step Kilo- 1000 Hecto- 100 Deka- Grams, liters,meters 10 base units 1 Deci- .1 Centi- .01 Milli- .001 Grams, liters,meters

A. SI Prefix Conversions Symbol Factor mega- M 106 kilo- k 103 BASE UNIT --- 100 deci- d 10-1 move left move right centi- c 10-2 milli- m 10-3 micro-  10-6 nano- n 10-9 pico- p 10-12

Metric Equivalents of Mass 1 kilogram (kg) = 1000 grams (g) 1 gram (g) = 1000 milligrams (mg) 1 milligram (mg) = 1000 micrograms (μg or mcg) Household Examples A pinch of salt 1 microgram 1 gram 1 milligram 1 kilogram

How Do I Use This? Start with the prefix of the first (known) unit. Step up or down to get to the prefix of the desired unit. Move the decimal the same direction & number of steps that were moved. If there is only one letter in the unit of measurement, then you start or stop on the base unit step.

525568 mm = ? m Millimeters are a very small amount of distance. You would not want to measure a large distance in a very small unit. To make the conversion, we start on the milli- step and go three steps to the left to get to the meter step. Therefore, the decimal in 525568 mm moves three places to the left, becoming 525.568 m.

The Stair-step Kilo- 1000 Hecto- 100 Deka- Grams, liters,meters 10 base units 1 Deci- .1 Centi- .01 Milli- .001 Grams, liters,meters

.00654 km = ? m Kilometers are a fairly large unit of distance. You would not want to measure a small distance in a large unit, so we need to convert it to a smaller unit, the meter. We would start on the Kilo- step and move three steps to the right this time, ending on the meter (base unit) step. Therefore, .00654 km becomes 6.54 m.

The Stair-step Kilo- 1000 Hecto- 100 Deka- Grams, liters,meters 10 base units 1 Deci- .1 Centi- .01 Milli- .001 Grams, liters,meters

Method 2: Conversion Cross Also called “factor-label” The problem is solved by cancelling the units (or “factoring” them out) cm3 g = g cm3

Conversion Cross Steps: 1. Identify starting & ending units. 2. Line up conversion factors so units cancel. 3. Multiply all top numbers & divide by each bottom number. 4. Check units & answer.

Conversion Cross 1 in = 2.54 cm 1 The key with the conversion cross is that the fractions must be equivalent. Ex. 1m = 100 cm 60 sec = 1 minute 365 days = 1 year 1 in = 1 2.54 cm

B. Dimensional Analysis How many milliliters are in 1.00 quart of milk?  qt mL 1.00 qt 1 L 1.057 qt 1000 mL 1 L = 946 mL ÷

Conversion Cross 1.5 lb 1 kg 2.2 lb 1000 g 1 kg 1 cm3 19.3 g = 35 cm3 You have 1.5 pounds of gold. Find its volume in cm3 if the density of gold is 19.3 g/cm3. Cross off units that cancel lb cm3 1.5 lb 1 kg 2.2 lb 1000 g 1 kg 1 cm3 19.3 g = 35 cm3 Each factor equals the conversion between the units