UNITS AND CONVERSIONS UNITS OF MEASUREMENT Units are

UNITS AND CONVERSIONS

UNITS OF MEASUREMENT • Units are incredibly important in the study of physics! • Example: The spider was 4 long. Was it… 4 millimeters? 4 inches? 4 kilometers?

STANDARD UNITS • SI Units (emphasized by our book) “Le Systeme International d’Unites” • Length – meter (m) • Mass – kilogram (kg) • Time – second (s)

METHOD FOR CONVERTING UNITS 1. Draw the box/grid. 2. Write the known quantity (with units) in the top left corner. Put a 1 in the bottom left corner. 3. Write the conversion factor to the right (with units). Put the part with the units matching the known quantity in the bottom, so that the units will divide out. 4. Cancel the units. Are the units left what you are looking for? If not, repeat step 3 and 4 with another conversion factor, again placing the parts so that units will divide out. 5. Multiply across the top and bottom separately. Divide the numbers and write your answer with units. • Example: If 1 thingy = 3 whatsits and 9 whatsits = 12 doohickeys, then doohickeys = ___ thingies? 100

PRACTICE 1. If 5 giants = 38 orcs, then 95 giants = ___ orcs? 2. If 40 diamonds = 520 gold bars and 1 pearl = 130 gold bars, then 20 pearls = _____ diamonds?

ENGLISH -> ENGLISH • Same steps as previous conversions. • Must memorize conversion factors! • Examples: 1. 2. 3. 4. Convert 4 yards to inches. Convert 15 ounces to pounds. Convert 15 fluid ounces to cups. Convert 3 years to seconds.

METRIC -> METRIC • Same process, time will be exactly the same. • Must know the prefixes! • Works the same for length (m), mass (g), and volume (L) • Examples: 1. Convert 145 cm to meters. 2. Convert 2. 3 kg to milligrams. 3. Convert 78. 3 d. L to hectoliters.

ENGLISH <-> METRIC • You will NOT have to memorize these conversion factors! They will be given on any quiz or test. • Examples: 1. Convert 35. 56 cm to inches. 2. Convert 0. 4 km to yards. 3. Convert 912 ounces to kilograms.

CONVERTING AREA •

CONVERTING VOLUME •

PRACTICE •