1. Unit 1 notes… Dimensional Analysis
Used to convert between units…

2. Unit 1 notes: Dimensional Analysis
Equivalence Statement: Relates the same amount (quantity) in 2 different units.
Ex cm = 1 inch.
conversion factors: relates equivalence in a ratio
2.54cm or
1 in
1 in___
2.54 cm

3. Dimensional Analysis-
Converting from a known unit to an unknown unit
3 steps:
1. What do I know? (underline)
2. What do I want to know? (circle)
3. How do I get there (equivalence statements)?

4. To convert… ●use equivalence statements
●Treat the units as variables/ numbers.
●Arrange the measurements so that they will cancel out.

5. Ex- A: A new baby weighs 7.8 lb, What is its mass in kilograms?
1kg = lb.
1 kg___
2.205 lb
= 3.5 kg
7.8 lb x / /

6. Let’s Try This! Equivalence Statement OR
= 8
Equivalence Statement 1 8 OR 8 1
These are the two possible conversion
factors that can be derived from the equivalence statement .

7. How many watermelons will there be for 136 bananas?
ANSWER: 1 X 8
This is the correct conversion factor to use
because is the denominator and it
will cancel out with the given unit.

8. How many bananas are equivalent to 12 watermelons?8
= 96 1
In this problem, this is the correct conversion factor
so the given unit will cancel with the
denominator of the fraction. X

9. Ex- B: How many seconds are in 2 days?
1 day = 24 hrs, 1 hr = 60 min, 1 min= 60s
x 24 hrs
1 day /
x 60 min
1 hr /
x 60s =
1 min s
2 days / / / /

10. Examples: Convert the following:
show all of your work!!!!
Appt A: feet to centimeters
(note: 1 ft = 12 in and 2.54 cm = 1in)

11. How did you do?
A feet to cm
4.98 ft x 12 in x cm = cm
1 ft in

12. Examples: Convert the following:
show all of your work!!!!
Appt B: seconds to hours
(note: 60 sec = 1min and 60 min= 1 hr)

13. How did you do?
B seconds to hours 
15000s x 1 min x 1 hr = 15000hr = 4.16 hr
60 s min

14. Examples: Convert the following:
show all of your work!!!!
Appt C: 75 km/hr to m/s
(note: 1000m = 1km, 1hr = 60 min, and 60 s = 1 min)

15. How did you do?
C. 75 km/hr to m/s 
75km x 1000m x 1 hr = 1min = m/s
hr km min 60s