1. Conversions How do we make conversions? Many equivalent measurements
1 m = 10 dm = 100 cm = 1000 mm

2. Conversion Factors Make a ratio of equivalent measurements
It is equal to one
100 cm = mm = 1
1 m m
Read as 100 cm per meter or
1000 mm per meter

3. Use conversion factors in problems where units need to be changed
When a number is multiplied by a conversion factor, the number may change but the size remains the same.

4. Conversion factors are defined as exact quantities and have unlimited sig figs
Can be written 2 ways:
1 l or ml
1000 ml l

5. Dimensional Analysis Best way to solve problems
How many quarters are in a roll of quarters worth $10?
$ quarters = quarters $1

6. Convert 157 cs to s
157 cs sec = cs
1.57 sec

7. Convert 42.7 l to ml
42.7 l ml =
1 1l
42,700 ml = 4.27 x 104 ml

8. Convert 8.25 x 102 g to ng
8.25 x 102 g 109 ng = g
8.25 x 1011 ng

9. Complex Problems Easier to do in several smaller steps
Convert 261 nm to mm
261 nm m mm =
nm m
2.61 x 10-4 nm

10. Convert km to dm
0.065 km 1000 m 10 dm =
km 1m
6.5 x 102 dm

11. Convert 642 cg to kg
642 cg g k =
cg 1000 g
6.42 x 10-3 kg

12. Convert 0.44 ml/ min to µl/sec
0.44ml 1 min l µl =
1min 60 sec ml 1 l
7.3 µl / sec

13. Convert 7.86 g/cm2 to mg/mm2
7.86g 1000mg cm =
cm g mm2
78.6 mg /mm2
1 cm = 10 mm
1 cm= 10mm

14. Convert 1.54 kg /l to g/ cm3
1.54 kg g l ml =
l kg ml 1cm3
1.54 g /cm3

15. A watch loses 0.15 s/min. How many minutes will the watch lose in 1 day?
0.15s 60 min 24 hr 1 min =
min 1 hr 1 day 60 sec
3.6 min /day