# III. Unit Conversions CH. 2 - MEASUREMENT III. Unit Conversions I (p. 40 - 42) II III C. Johannesson A. SI Prefix Conversions 1. Find the difference between the exponents of the two prefixes. 2. Move the decimal that many places. To the left or right? C. Johannesson

A. SI Prefix Conversions 532 m NUMBER UNIT 0.532 km = _______ = C. Johannesson NUMBER UNIT A. SI Prefix Conversions move right

move left Prefix mega- Symbol M Factor 106 kilo- k 103 BASE UNIT ---

100 deci- d 10-1 centi- c 10-2 milli- m 10-3 micro-

10-6 nano- n 10-9 pico- C. Johannesson p 10-12 A. SI Prefix Conversions 1) 20 cm =

0.2 ______________ m 2) 0.032 L = 32 ______________ mL 3) 45 m = 45,000 ______________ nm 4) 805 dm = 0.0805 ______________

km C. Johannesson B. Dimensional Analysis The Factor-Label Method Units, or labels are canceled, or factored out g cm 3 g cm 3 C. Johannesson B. Dimensional Analysis 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. C. Johannesson B. Dimensional Analysis Lining up conversion factors: 1 in = 2.54 cm =1 2.54 cm 2.54 cm 1 in = 2.54 cm 1= 1 in 1 in C. Johannesson B. Dimensional Analysis How many milliliters are in 1.00 quart of

milk? qt mL 1.00 qt 1L 1000 mL 1.057 qt 1L C. Johannesson = 946 mL

B. Dimensional Analysis You have 1.5 pounds of gold. Find its volume in cm3 if the density of gold is 19.3 g/cm3. lb cm3 1.5 lb 1 kg 1000 g 1 cm3 2.2 lb 1 kg 19.3 g C. Johannesson = 35 cm3

B. Dimensional Analysis How many liters of water would fill a container that measures 75.0 in3? in3 L 75.0 in3 (2.54 cm)3 (1 in)3 1L 1000 cm3 C. Johannesson = 1.23 L B. Dimensional Analysis 5) Your European hairdresser wants to cut your

hair 8.0 cm shorter. How many inches will he be cutting off? cm in 8.0 cm 1 in 2.54 cm = 3.2 in C. Johannesson B. Dimensional Analysis 6) Taft football needs 550 cm for a 1st down. How many yards is this? cm 550 cm

yd 1 in 1 ft 1 yd 2.54 cm 12 in 3 ft C. Johannesson = 6.0 yd B. Dimensional Analysis 7) A piece of wire is 1.3 m long. How many 1.5-cm pieces can be cut from this wire? cm pieces

1.3 m 100 cm 1m 1 piece 1.5 cm C. Johannesson = 86 pieces