1. Do Now
Grab the lab handout on the desk and work on pre-lab questions (1-6)
Take out HW to be checked
Sig Figs Quiz: FRI 9/4
Unit 1 Test THURS 9/10, FRI 9/11

2. Agenda: Measurement Lab: Sci Notation, Unit Conversions
You may start at any station
Make sure you estimate your measurements to the proper number of decimal places
Round all calculations at the end to proper # of sig figs!
Sci Notation, Unit Conversions
Homework: finish Sci Not/Unit Conv handout

3. Telephone
602,000,000,000,000,000,000,000
6.02 x 1023

4. Scientific Notation
Scientific notation is used to express very large or ­very small numbers more easily.
It is written as a (decimal between 1 & 10) x 10 raised to an exponent

5. How to express a number in terms of scientific notation:
1. Move the decimal point of your number so that you have a decimal between 1 and 10

6. How to express a number in terms of scientific notation:
2. Count the number of spaces (n) and which direction you moved the decimal point

7. How to express a number in terms of scientific notation:
3. If you moved the decimal point to the left multiply (x) your decimal by 10n
360,000  3.6 x 105
If you moved the decimal point to the right, multiply (x) your decimal by 10—n
 3.7 x 10—4

8. Category
Normal Number
Scientific Notation
Population of the World
7,125,000,000 people
Distance from the Earth to the Moon
240,000 miles
Raindrops in a Thundercloud
6,000,000,000,000 drops
Density of Oxygen
g/cm3
Mass of a Dust Particle kg

9. How to express a value given in scientific notation as a normal number:
1. Identify the exponent
3.6 x 105: exponent 5
3.7 x 10—4: exponent –4

10. How to express a value given in scientific notation as a normal number:
2. If the exponent is a positive number, move the decimal point the same number of places to the right
3.6 x 105: move decimal 5 places to the right

11. How to express a value given in scientific notation as a normal number:
3. If the exponent is a negative number, move the decimal point the same number of places to the left.
3.7 x 10—4: move decimal 4 places to the left

12. Category
Normal Number
Scientific Notation
Speed of Light
3.00 x 108 m/s
Distance from the Earth to the Sun
9.3 x 107 miles
Cells in the Human Body
1.0 x cells
Water on Earth’s Surface
1.40 x 108 square miles
Diameter of a Grain of Sand
2.4 x inches

13. x1000
x10
x10
x10
x10
x10
x10
x1000
x1000
Prefixes at the top of the chart represent a larger amount or quantity.
Prefixes at the bottom of the chart represent a smaller amount or quantity.  

14. Dimensional Analysis (aka Factor-Label Method, Unit-Factor Method)
Can be used to convert from one unit to another; it is based on the idea of cancelling out units!
It is super important to WRITE OUT ALL UNITS when doing this!

15. Ex: Convert 1609 meters into kilometers

16. Ex: Convert 1609 meters into kilometers

17. Ex: Convert 1609 meters into kilometers

18. Ex: Convert 1609 meters into kilometers