NOTES
Ch.1- The Methods of Science
OBJECTIVE: IDENTIFY THE STEPS USED TO SOLVE PROBLEMS
Science-Is a process that used observation and investigation to gain knowledge about events in nature. It is a method for studying the
natural world.
3 Major Categories of Science:
(1) Biology- the study of life
(2) Earth Science- Investigates Earth and space
(3) Physical Science- Deals with matter and energy
Scientific Method- An organized set of investigation procedures. The steps are:
1. Observation- Ask a question (State the Problem)
2. Gather information- Do research
3. Form a hypothesis
Hypothesis- A testable statement. Use “if and then” statements.
Example: If silicon is used, then the space shuttle will not burn.
4. Experiment-Test the hypothesis (may need to repeat several times)
Can test a hypothesis by making observations or building a model or performing an experiment.
Model- Represents an idea, event or object to help people understand it.
Experiment- Tests the effect of one thing on another using controlled conditions
An experiment has at least two variables. A variable- A factor (characteristic) that can change.
Parts of an experiment:
(1)
(2)
(3)
(4)
(5)
dependent variable- Variable that depends on the independent variable.
Independent variable- Variable that can change and affects the dependent variable.
Constant- A factor that does not change.
Control Group- Group where the standard by which the test results can be compared. It contains the constants.
Experimental Group- Group where the independent variable occurs.
Example of an Experiment
Problem: If this vaccine is used, will it cure cancer?
Hypothesis: If the female takes the vaccine, then she will be cured (dependent variable).
Control Group (constants)
Experimental Group
Healthy Diet
Healthy Diet
Exercise
Exercise
8 Hours of Sleep
8 Hours of Sleep
No Vaccine
Vaccine (independent variable)
5. Analyze data- Record observations and organize the data
6. Draw conclusions (Hypothesis is either supported or not supported)
The Scientific Method Video
https://www.youtube.com/watch?v=SMGRe824kak
Theory- An explanation of things or events based on knowledge gained from many observations and investigations. It is not a guess.
Scientific Law- Is a statement about what happens in nature and that seems to be true all the time. Laws tell you what will happen
under certain conditions, but they do not explain why or how something happens.
Technology- The application of science to help people.
Standards of Measurement
International System of Units (SI)- is the universally accepted version of the metric system.
Each SI measurement has a base unit.
Quantity Measured
Length
Mass
Time
Electric Current
Temperature
Amount of Substance
Intensity of Light
Unit
meter
kilogram
second
ampere
kelvin
mole
candela
Symbol
m
kg
s
A
K
mol
cd
SI Prefixes- Used with the names of the units to indicate what multiple of ten should be used with the units. For example, the prefix
kilo means 1,000. That means that one kilometer equals 1,000 meters.
Micrometer (µ)means 0.000001
Nanometer (n) means 0.000000001
Length is the distance between two points. Length is measured using meters as its unit.
Volume is the amount of space occupied by an object. To measure the volume of a rectangle (i.e. brick) measure its length, width, and
height. ( V= l x w x h )
Liquids are measured in liters or cubic centimeter cm3 . One liter is equal to 1,000 mL
Mass- Is the measurement of the quantity of matter in an object. It is measured by grams.
Matter- Is anything that takes up space.
Density- Is the mass per unit volume of a material. Density is found by dividing an object’s mass by the object’s volume. ( D= m/v).
m is measured in grams and v is measured in cm3
Time- Is the interval between two events. The SI unit for time is the second.
Temperature- Is measured on the Celsius (C) scale. The freezing point of water is 0 °C. The boiling point of water is 100 °C.
The SI unit of temperature is the kelvin (K). Zero on the Kelvin scale is the coldest possible temperature, also known as absolute zero.
This is equal to -273°C.
K = °C + 273
Metric System Video:
https://studyjams.scholastic.com/studyjams/jams/math/measurement/units-of-measurement.htm
Line Graphs
Line Graphs show any relationship where the dependent variable changes due to a change in the independent variable. Line
graphs show how a relationship between variables changes over time.
Bar Graphs
Bar graphs are used when comparing information collected by counting.
Bar Graph Activity
https://studyjams.scholastic.com/studyjams/jams/math/data-analysis/bar-graphs.htm
Circle Graphs
Circle graphs or pie graphs show how some fixed quantity
is broken down into parts. The circular pie represents the
total. The slices represent the parts and usually are
represented as percentages of the total.
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Video on Bar Graphs:
https://www.khanacademy.org/math/cc-third-grade-math/represent-and-interpret-data/imp-bar-graphs/v/creating-pictureand-bar-graphs-2-exercise-examples
Graphing Games:
Create Line Graphs - Grade 6 - Practice with Math Games