1. Section 1.3
Measurement

2. Key concepts for 1.3 Why is scientific notation useful?
What units do scientists use for their measurements?
How does the precision of measurements affect the precision of scientific calculations?

3. Measurement
Science would be impossible if we didn’t have ways of measuring things.
Examples of things we measure everyday: passage of time (clock watchers) amounts of money.

4. Scientific Notation
When scientists work with numbers they usually work with very large or very small numbers.
The speed of light is about 300,000,000 meters per second.
A snail has been clocked at a speed of meters per second.

5. Scientific Notation
Very large or very small numbers can be difficult to work with.
Scientific Notation makes these numbers easier to work with.
The numbers become shorter and are expressed by using a power of 10

6. Scientific Notation The speed of light 300,000,000 becomes 3 x 108
Where did I get the 8?
The speed of the snail becomes x 10-4
How did I get 4? And why is it negative?

7. Scientific Notation makes very large or very small numbers easier to work with.
Scientists can now add, subtract, multiply, and divide these numbers with ease.
You have to know how to convert numbers to scientific notation.

8. Page 15 shows how to perform calculations using the scientific method.
You will not have to perform these calculations in this class.
They could be an extra credit opportunity at a later time.

9. SI units of measurement
(metric system)

10. Mars Goof
Scientists use the SI (metric) system to communicate with each other and avoid culture barriers.
Mess ups still occasionally happen.
The Mars Climate Orbiter was built in Denver but controlled in California.
The final jet propulsion code was needed to put it in orbit around Mars.
Denver sent specifications in English units, pounds of force.
California assumed it was in Newtons.

11. SI System
Scientists use a set of measuring units called SI or the International System of Units.
In order for measurements to make sense they must have a UNIT.
Take a look at pages 16 and 17