1. Dimensional Analysis Organized method of problem-solving
Used in chemistry, physics, engineering, and medicine
Communicates the path to scientists that follow your work
Records your own path for your future use

2. Calculate the number of minutes in 3.61 hours.
Dimensional Analysis
Calculate the number of minutes in 3.61 hours.
*Note: Use the number given in the question to determine the number of sig figs in your answer.
1. Write the given.
2. Draw the chart.

3. 3. Think of a relationship: 1 hr = 60 min 5. Cancel units diagonally.
Dimensional Analysis
Calculate the number of minutes in 3.61 hours.
*Note: Use the number given in the question to determine the number of sig figs in your answer.
3. Think of a relationship: 1 hr = 60 min
4. Divide the relationship in ½ at the = sign.
5. Cancel units diagonally.

4. 6. Add the rest of the relationship.
Dimensional Analysis
Calculate the number of minutes in 3.61 hours.
*Note: Use the number given in the question to determine the number of sig figs in your answer.
6. Add the rest of the relationship.
Count sig figs in the given. Round
the answer to that number of sig figs.

5. How many centimeters are in 4.2 inches?
Dimensional Analysis
How many centimeters are in 4.2 inches?
*Note: Use the number given in the question to determine the number of sig figs in your answer.

6. How many centimeters are in 4.2 inches?
Dimensional Analysis
How many centimeters are in 4.2 inches?
*Note: Use the number given in the question to determine the number of sig figs in your answer.

7. Realize that we don’t know just one step from weeks to seconds.
Dimensional Analysis
Multi-Step Problems
Calculate the number of seconds in two weeks.
Realize that we don’t know
just one step from weeks to seconds.

8. Dimensional Analysis Multi-Step Problems Start as usual.
Calculate the number of seconds in two weeks.
Start as usual.

9. Dimensional Analysis Multi-Step Problems Extend your table.
Calculate the number of seconds in two weeks.
Extend your table.

10. Continue adding relationships.
Dimensional Analysis
Multi-Step Problems
Calculate the number of seconds in two weeks.
Continue adding relationships.

11. Add as many conversions as needed.
Dimensional Analysis
Multi-Step Problems
Calculate the number of seconds in two weeks.
Round to 1 sig fig.
Add as many conversions as needed.

12. Notice the use of the bottom space.
Dimensional Analysis
Multi-Step Problems
Convert the density of 0.58 g/mL to lb/gallon (1 L = qt and 4 qt = 1 gal; 1kg = 2.2 lb)
Notice the use of the bottom space.

13. Ignore the bottom unit for a moment.
Dimensional Analysis
Multi-Step Problems
Convert the density of 0.58 g/mL to lb/gallon (1 L = qt and 4 qt = 1 gal; 1kg = 2.2 lb)
Ignore the bottom unit for a moment.
Concentrate on converting the top unit.

14. Continue converting the top. Stop when you get to lb…the goal.
Dimensional Analysis
Multi-Step Problems
Convert the density of 0.58 g/mL to lb/gallon (1 L = qt and 4 qt = 1 gal; 1kg = 2.2 lb)
Continue converting the top.
Stop when you get to lb…the goal.

15. Now, focus on the bottom units.
Dimensional Analysis
Multi-Step Problems
Convert the density of 0.58 g/mL to lb/gallon (1 L = qt and 4 qt = 1 gal; 1kg = 2.2 lb)
Now, focus on the bottom units.
It is OK to cancel units from a distance.

16. Continue adding until you reach the goal.
Dimensional Analysis
Multi-Step Problems
Convert the density of 0.58 g/mL to lb/gallon (1 L = qt and 4 qt = 1 gal; 1kg = 2.2 lb)
Continue adding until you reach the goal.