1. The Methods of Science
Integrated Science 9

2. Science
Science is a process that uses observation and investigation to gain knowledge about events in nature.
Major categories:
Life science
Living things
Earth Science
Earth
Space
Physical Science
Matter
Energy

3. Investigating our World
Scientists learn new information about the natural world by performing investigations.
Can be done in a variety of ways:
Observing and recording
Experiments
Using Models
The Scientific Method described the procedure commonly followed in scientific investigations

4. Scientific Method Six common steps used in investigation
State the Problem
Gather Information
Form a hypothesis
Test the hypothesis
Analyze Data
Draw conclusions
Not all steps will be used every time
Some steps may be repeated
Some new steps may be added
The scientific method is not a rigid process

5. Let’s break it down… Stating the problem
State the problem in a form of a question
Make sure the question asks something that is testable

6. Testable Questions Why do people ask questions?
To a scientist, what do you think makes a good question?
What types of questions do you think aren’t suitable for scientific investigation?

7. Let’s Break it Down… Researching and Gathering information
Research is necessary to formulate a reasonable hypothesis
Sources of information:
Textbook
Articles
Expert
Reference books
Observations

8. Let’s break it down…(cont)
Forming a hypothesis
Make an educated guess to answer the question you are investigating
Scientists frequently create a hypothesis with little or no information
As data is collected, a hypothesis is often refined
Testing the hypothesis
Experiments or observation
Experiments
Have only 1 independent variable
All other variables are held constant

9. Let’s Try That…
An experiment is set up to determine what factor causes the greatest amount of liquid to evaporate.
Three containers of the same size each contain 100 mL of boiling water.
One container is steel, one is brass, and the third is aluminum.
The containers are allowed to sit for 20 minutes.
What is the independent variable?
How many controlled factors are there?

10. Let’s break it down…(cont)
Analyzing Data
Using tables and charts
Share data with others
Draw conclusions
Does the data support the hypothesis?
What do I need to do now?
Rules of Thumb:
Don’t jump to conclusions
The simplest solution is usually correct

11. Now we’ll put it all together…
In 1912, farmers in California found that it was cheaper to pick all the oranges at once regardless of whether they were ripe.
The oranges were placed in a small room heated with kerosene lamps and the oranges would ripen in a few days.
At some point, the farmer used an electric heater instead of kerosene lanterns. The oranges no longer ripened.
When switching back to kerosene, the oranges ripened.
This was found to be true of other citrus.
The farmers wondered what was so special about the kerosene lanterns?

12. Here we go… What is the question? What type of research would you do?
Design an experiment.
What is the independent variable?
What are the controlled factors?
Analyze the results
Draw a conclusion

13. Observations
Test Your Observation Skills
M&M Lab
Variables Worksheet

14. Visualizing with Models
Sometimes when observing something that is too large, too small, or too time consuming, we need to use models
Models have been used frequently throughout history.
Models can be something you can touch or many models are created using computers.
Dams and Levees
Cowpea Mosaic Virus

15. Scientific Theories and Laws
A theory is an explanation of things or events based on knowledge gained by many observations and investigations
Strongly supported hypotheses can become theories
Scientific Laws are statements of what happens in nature
Laws do not offer explanation as to why
Theories Explain Laws!

16. Standards of Measurement
SI (International System of Units) is the share language for measurement in science
Based on the metric system
Uses multiples of 10
Each type of measurement has a base unit
Lengthmeter
Masskilogram
Timesecond
Electric currentampere
Temperaturekelvin
Amount of a substancemole
Intensity of lightcandela

17. SI Prefixes
The SI base units are not always of convenient size for a particular measurement.
The meter would be too big for reporting the thickness of this page
The meter would be too small for the distance from Chicago to Detroit
SI includes a series of prefixes, each of which represents a power of 10.
These allow us to reduce or enlarge the SI base units to convenient sizes. 

18. Conversions A box weighs 1.25 kg. How many grams is that?
Metric Conversion Ladder
A box weighs 1.25 kg. How many grams is that?
Kilogram (kg) is larger than gram (g)
You need to multiply (shift decimal to the right)
3 steps (3 zeros)
1.25 x 1000 = 1,250 grams

19. Let’s try a few…
Conversion Worksheet

20. Measuring Distance
Choose a unit of length that is appropriate for what you are measuring
For example,
cm for length of pencil
m for length of classroom
Helps avoid using large digit numbers

21. Remember: You have to multiply the numbers AND the units
Measuring Volume
The amount of space an object occupies is volume.
Measure length, width, and height and multiply the three numbers
length x width x height = volume
Example: 10 cm x 10 cm x 10 cm = 1000 cm3
Remember: You have to multiply the numbers AND the units
Liquid volume is often measured in liters
1 mL = 1 cm3
1000 cm3 is 1000 mL

22. Measuring Matter Matter is anything that has mass and takes up space.
To measure mass, we use mass and volume.
Mass and volume can be expressed as a ratio called density
Density is a combination of two SI units.
Combining two or more SI units results in a derived unit.
Can you think of other examples?

23. Accuracy and Precision
Accuracy is how close a measured value is to the actual (true) value.
Correctness
Precision
Precision is how close the measured values are to each other.
Repeatability

24. Communicating with Graphs
Scientists often use graphs and charts to display their result in order to better identify patterns
Graphs are useful for displaying numerical information.
Different graphs are useful for different types of information
Line Graph
Bar Graph
Circle Graph

25. Line Graphs
Line graphs are useful whenever a dependent variable is changing due to a change in a independent variable
Dependent variables are y-axis
Independent variable are the x-axis

26. Bar Graphs
Bar graphs are useful for comparing information collected by counting.

27. Circle Graphs
Circle graph, or pie charts, are use to show how some fixed quantity is broken down
The pieces of the pie represent a percentage of the total