1. Introduction to science
Chapter 1

2. 1.1 The nature of science

3. The Nature of Science How does science take place?
Scientists investigate
Scientists plan experiments
Scientists observe
Scientists always test results
Science has many branches
Science and technology work together

4. What is Science?
Science is the process that uses observation and investigation to gain knowledge about events in nature
Science has many branches
Biological
Physical Science
Earth Sciences

5. Branches of Science

6. Biological Science Biological Science – science of living things
Also called Life Science or Biology
Botany- science of plants
Zoology- science of animals
Ecology- science of balance in nature
Medicine
Agriculture

7. Physical Sciences Physical Science- science of matter and energy
Chemistry- science of matter and its changes
Physics- science of forces and energy

8. Earth Sciences Earth Science- science of Earth
Geology- science of the physical nature and history of the Earth
Meteorology- science of the atmosphere and weather

9. Technology- is the application of science
Technology and science depend on one another
Scientists who do experiments to learn more about the world are practicing pure science

10. Scientific Law vs. Scientific Theory
Scientific Law is a rule of nature that sums up related observations to describe a pattern in nature
A law tells us how things work
Allows us to make predictions about how a system will behave
Does not explain how a process takes place
Example: Law of Gravity

11. Scientific Law vs. Scientific Theory
Scientific Theory is an explanation based on experiments most logical explanation
They are always being questioned and examined
Theories must:
Explain observations clearly and consistently
Repeatable
Predictable
Example: Black Hole Theory

12. Scientific Law vs. Scientific Theory
Laws and Theories are always being tested
Sometimes theories have been changed or replaced completely when new discoveries are made

13. Models
Scientific model- representation of an object or event that can be studied to understand the real object or event
Models represent things that are too small, big or complex to study easily
Models can be mental pictures or even mathematical representations.

14. 1.2 The way science works

15. The Way Science Works
Scientists used the scientific method to practice science
Scientific method is an organized set of investigation procedures used by scientists

16. Scientific Method
Hypothesis is an educated guess or testable prediction
Experiment is an organized procedure for testing the hypothesis
Control is the standard for comparison
Constant is the factor that does not vary in an experiment

17. Scientific Method cont.
Independent variable is the factor that is adjusted by the experimenter
Goes on the x-axis
Dependent variable is the factor whose value depends on the independent variable
Goes on the y-axis

18. Scientific Method cont.
Share Results
Ask a question
Conclusion
Gather & Analyze Data
Further Research
Research
Form Hypothesis
Design Experiment

19. Units of Measurement
International System of Units (SI) Standard system of measurement used worldwide

20. Units of measurement SI units are used for consistency
SI prefixes are for very large and very small measurements
Prefix
Symbol
Meaning
Multiplying Factor
giga- G
billion
1,000,000,000
mega- M
million
1,000,000
kilo- K
thousand
1000
deci- D
tenth
0.1
centi- C
hundredth
0.01
milli-
thousandth
0.001
micro- μ
millionth
nano- n
billionth

21. Making Measurements Length – Distance between two points Volume
– The amount of space occupied by an object
Mass
– Amount of matter in an object
Density
– Mass per unit volume of a material
Time
– Interval between two occurring events

22. 1.3 Organizing data

23. Presenting scientific data
Graph- a visual display of information or data
Types of Graphs:
Line
Bar
Circle or Pie

24. Line graphs are best for continuous changes
Shows trends or how the data changes over time

25. Bar graphs are best to compare items
Bar graphs often make clear how large or small the differences in individual vales are.

26. Pie charts or circle graphs are ideal for displaying data that are parts of a whole.
Usually we use percentages

27. Writing Numbers in Scientific Notation
Scientific notation- a method of expressing a quantity as a number multiplied by 10 to the appropriate power.
It is the short hand way to represent where the decimal place is located in a measurement or value.

28. Positive exponents means to move decimal place to the right
Example:
5.4× 10 4 =54,000
Negative exponents means to move decimal place to the left
2.54× 10 −3 =

29. Scientific notation rules
Adding and Subtracting
Powers need to be the same and the answer will have the same power.
Example:
4.23× × 10 4 =2.01× 10 4

30. Scientific notation rules
Multiplying and Dividing
Powers do not need to be the same
Multiplying -> You multiply the base number and add the exponents
Dividing -> You divide the base number and subtract the exponents

31. Multiplication Example
2.23× 10 3 ×4.44× 10 6 =
Step 1: Multiply base number
2.23 × 4.44 =
Step 2: Add exponents
3 + 6 = 9
Step 3: Put back together
9.9012× 10 9

32. Divison Example
6.02× 10 6 ÷1.02× 10 3 =
Step 1: Divide base number
6.02 ÷1.02 =5.90
Step 2: Subtract exponents
6 −3 =3
Step 3: Put back together
5.90× 10 3

33. Using Scientific Notation
Your state plans to buy a rectangular tract of land measuring 5.36× 10 3 m by 1.38× 10 4 m to establish a nature preserve. What is the area of this tract in square meters?

34. Precision vs. accuracy Precision means the exactness of a measurement
Accuracy a description of how close a measurement is to the true value of the quantity measured