1. Chapter 1: Nature of Science
What is a scientist and what does he do?
Scientists investigate
Scientists plan experiments
Scientists observe
Scientists test results
SCIENTISTS ASK GOOD QUESTIONS!

2. Pure Science vs. Technology
Pure Science is scientific knowledge gained by observation and experiment.
Technology is the application of pure science to meet human needs.

3. Scientific Theory
A scientific theory is a tested, explanation of a natural event. [Theories have not been proven]
A theory must explain observations simply and clearly.
Experiments that illustrate the theory must be repeatable.
You must be able to predict from the theory.

4. Scientific Law
A scientific law is a description of a natural event. [Laws have been proven]
Newton’s law of gravity
Newton’s laws of motion
Hooke’s law
Kepler’s laws of planetary motion
Etc.

5. Section 1.1 Review:
Explain how science and technology depend on each other.
How does a scientific law differ from a theory?
Pick a common phenomenon and develop a theory about it, what kind of experiment could you do to test the theory?

6. Section 1.2 The Way Science Works
Critical thinking is a basic skill of a scientist. It is applying logic and reason to observations and conclusions.
The scientific method is a series of logical steps to follow in order to solve a problem or answer a question. (pg. 13 fig 1-12)

7. Scientific Method [5 steps]
Make an observation
Form an hypothesis
Make predictions
Test the hypothesis
Draw a conclusion

8. Systeme International d' Unites – SI Measurement System
Base Units of SI System (total of 7)
Length – Meter, m
Mass – Kilogram, kg
Time – Second, s
Temperature – Kelvin, K
Electric current – ampere, A
Amount of substance – mole, mol
Luminous intensity – candela, cd

9. Systeme International d' Unites – SI Measurement System
Derived Units of SI System (hundreds)
Force – Newton, N
Area – Square meters, m2
Volume (liquid)– Liter, L.
Velocity – meters/second, m/s
Acceleration - meters/second/second, m/s2
Pressure- N/m2

10. Examples of SI Measurement System units
Length – meter, m
Force or weight – Newton, N
Mass – kilogram, kg
Area – m2
Volume – m3
Density – g/cm3
Time – second, s
Temperature – degrees Celsius, oC

11. Examples of English Measurement System units
Length – feet, ft
Force or weight – pounds, lbs
Area – square feet, ft2
Volume – cubic feet, ft3
Density – pound per cubic feet, lb/ft3
Time – seconds, s
Temperature – degrees Fahrenheit, oF
Etc.

12. Scientific Notation
In many branches of science, some numbers are very small, while others are quite large. To conveniently express these numbers, scientists use a type of shorthand called scientific notation to express the number as a multiplier and a power of 10.
= x 10-6
422,000,000,000,000 = x 1014

13. Significant Figures
For numbers with no decimal point, start from the “atlantic” right hand side and count all digits beginning with the first non-zero digit.
Ex: has two sig. figs.
For numbers with a decimal point, start from the “pacific” left hand side and count all digits beginning with the first non-zero digit.

14. Scientific Notation
Scientific Notation: a value written as a simple number multiplied by a power of 10.
Ex: = = 10-3
Why is one positive and the other negative?
Very large #’s are positive and very small #’s are negative.

15. Metric Prefixes Prefix Symbol Meaning kilo- k 1000 hecto- h 100
deka- da 10
Base Unit
deci- d 0.1
centi- c 0.01
milli- m
micro- m
nano- n

16. Meaningful Metric Prefixes
Prefix Symbol Meaning
tera- T or 1012
giga- G or 109
mega- M or 106
kilo- k or 103
milli- m or 10-3
micro- m or 10-6
nano- n or 10-9
pico- p or 10-12

17. Converting temperature
Conversion of Fahrenheit to Celsius
oC = 5/9 [oF ]
Conversion of Celsius to Fahrenheit
oF = [9/5 x oC]

18. Section 1.2 cont..
A conversion factor is used to convert between units.
Ex: How many centimeters are in 1.85 inches?
1.85 in x [2.54 cm/1 in]
4.70 cm
Ex: How many

19. Section 1.2 cont… How to set up a conversion factor:
#1: Always write what you are given FIRST!
#2: Put what you are looking for on top of the conversion line.
#3: Put what you are trying to cancel out on the bottom of the conversion line.

20. Conversion Factor Process
Ex: Write 550 millimeters as meters
#1: given: 550 millimeters
#2: looking for meters
#3: want to cancel millimeters
550 mm x 1 m/1000 mm
Calculate: 550 x 1 / 1000 = 0.55 m

21. Conversion Practice Convert the following: 1.6 kilograms to grams
2500 milligrams to kilograms
0.4 millimeters to micrometers
2800 millimoles to moles
6.1 amperes to milliamperes
1600 g
.0025 Kg
400 mm
2.8 mol
6100 mA

22. Section 1.2 Making Measurements
There are many observations that rely on quantative measurements. The most basic scientific measurements generally answer how big, how much, or how much time.
We use length, mass, time, and volume as quantative measurements in labs.
Remember:
Length = meters
Mass = grams
Volume = liters or cubic centimeters cm3

23. Organizing Data There are several ways to organize lab data.
Data Chart: Good way of keeping track of something over time or making several readings on a topic. Usually done as raw data.
Graphs: A good way to organize your raw data and show trends, inferences, or results.

24. Graphs There are several types of graphs.
Line graph: shows change over time
Bar graph: good for comparing data for several individual items or events
Pie chart: ideal for displaying data that are parts of a whole

25. Line Graph
Independent variable: goes on the x axis. That is the bottom of the graph. Here the time in days is the independent variable. This variable is determined by the experimenter.
Dependent variable: what is changing in the experiment. This is not determined by the experimenter.

26. Bar Graph
What you’re comparing goes on the x axis

27. Pie Chart