chapter 1 science skills 1.1 what is science? throughout history, humans have had a strong sense of...
TRANSCRIPT
Chapter 1
Science Skills
1.1 What is Science?
Throughout history, humans have had a strong sense of curiosity.
Science: is a system of knowledge (process) and the methods you use to find that knowledge.
Goal of science is to understand the world around us
Science begins with curiosity and ends with discovery. Scientific Method
1.1
Technology: is the use of knowledge to solve practical problems. Long Distance Communication = Telephone Time consuming math calculations =
calculator Science and technology are interdependent.
Advances in one lead to advances in another. Example Evolution of telephones… page 3
1.1 Branches of Science
Natural Science: can be broken down into 3 branches. (make a
graphic organizer using Inspiration)
1. Physical Science: focuses on non-living things. Physical Science can be broken down into 2 fields:
Chemistry: is the study of the composition, structure, properties, and reactions of matter.
Physics: is the study of matter and energy and the interactions between the two through forces and motion.
1.1 Branches of Science
2. Earth and Space: is the study of Earth and space by applying chemistry and physics.
Geology: is the study of the origin, history, and structure of Earth.
Astronomy: is the study of the universe beyond Earth, including the sun, moon, planets, and stars.
3. Life Science or Biology: is the study of living things (life science)
Zoology= animals Botany= plants
1.1 Big Ideas of Physical Science
The universe – very old and very big. The universe – mostly space. Matter: anything that takes up space
(has both mass and volume) All matter – made of atoms. World – full of forces and motion. Energy exists in many forms.
1.2 Scientific Method
Scientific Method: organized plan for gathering, organizing, and communicating information. (A systematic approach to problem solving)
Objective: judgment without bias or prejudice (detatched) (without emotion)
Subjective: judgment with bias, feelings, emotions, and or prejudices
Scientifc method should be OBJECTIVE!
The goal of science– to solve a problem to better understand an observed event.
(The world around us)
Steps of the Scientific Method
1. State the problem/Form Question:
2. Gather Information: gathering information using your senses. (observations & research)
1.2 Scientific Method
3. Form a hypothesis: Hypothesis: proposed answer to a
problem. (If –then statement) Must be testable Good Words = hypothesize, suggest,
propose Bad words = think, believe, in my
opinion
1.2 Scientific Method4. Testing a Hypothesis:
Experiments test the hypothesis. Variable: any factor that can
change during an experiment. Manipulated/ independent variable: is the
variable we (scientists) change intentionally. Responding/dependent variable: changes in
response to the manipulated variable. (what we measure)
Constant: parts of ex. that don’t change Control: doesn’t contain the manipulated variable
Graphing Independent/dependent variables Normal graph: The x-axis is the
independent variable and the y-axis is the dependent variable.
Variables:Independent Variable: Type of Band-AidDependent Variable: Time it takes Band-Aid to fall off
Review of variables
A good experiment attempts to control all variables except the variable(s) that are being manipulated to see if a change can be observed and a cause and effect relationship can be reasoned
Variable A property or condition that can change.A variable may or may not cause a significant change.
Manipulated variable is the variable that the experimenter decides to change to see if there is or is not an effect.
Responding variable is the variable that will change as a result of the change in the manipulated variable. It may also be observed and or measured to determine the quantity or quality of change.
When we plot information on a graph the manipulated variable always is plotted on the X - axis and the responding variable is always plotted on the Y - axis.
Independent variable is another name for manipulated variable. It is independently selected by the experimenter to be manipulated.
Dependent variable is watched by the experimenter and will respond to the manipulated or independent variable if there is a relationship.
These relationships can be represented on a chart or graph:
Controlled Experiment: only one manipulated variable is deliberately changed at a time. (everything else stays the same)
Data: information gathered Measurements (time, length, width, mass,
temp, volume, density, etc) Observations (color, size, shape, texture)
(Tables, graphs, pie charts, lists, etc.)
1.2 Scientific Method
5. Analyzing Data Scientists decide if data supports the
hypothesis Tables, graphs, etc. show other people
what happened6. Conclusion:
Is a summary of exp. with results If data doesn’t support hypothesis, then
revise it & test again If data supports the hypothesis, test again
to validate results
1.2 Scientific Method
7. Developing a Theory: Scientific Theory: a well-tested explanation
for a set of observations or experimental results.
Theories are supported, not proven Scientific Law: statement that summarizes
a pattern found in nature. Describes an observed pattern without
trying to explain it. Ex. Gravity.
1.2 Scientific Models
Scientific models: used to understand things that are too difficult to observe directly. Model of the atom Model of the universe Model of a city Model cars/planes
1.3 Measurement
Scientific notation – Makes it easier to work with very large or very small numbers
Multiples of 10
Negative exponent = less than 1 Positive exponent = greater than 1
Practice
Write the following in scientific notation/normal number.
1. 2300.00
2. 1.635 X 10-2
3. .0035
4. 5.67 X 105
1.3 SI Units (Metric System)
Scientists use SI (International System) Length: straight-line distance between 2
points (measured with ruler/m. stick) Mass: amount of matter in an object
(measured with scale/balance)
Volume: amount of space an object takes up Formulas on study sheet (box, cyl, irr.)
Solids = cm3
Liquids = mL
Open book to page 16 Base units (Page 16) Derived Units (Page 16)
Density: mass per unit of volumeD=m/v
1.3 Measurement
Metric Prefixes Conversion Factor: is a ratio (fraction) of
equal measurements used for a conversion 1 km = 1,000 m 1 m = 100 cm 1 m = 1,000 mm Example Problems
1.3 Limits of Measurement
Precision: is how exact a measurement is Significant digits: are all the digits in a
measurement, plus the last estimated digit. The more significant digits = more precise
Accuracy: closeness to the actual measurement
Temperature: measured with a thermometer Temperature table: pg. 20
1.4 Presenting Scientific Data
Scientists organize data into tables and graphs Data Table: information arranged into a table,
this info can then be expressed as: Line Graph- good to show change in variables,
Slope (rise/run) shows a relationship between manipulated variable & responding variable)
Bar Graph- good to compare groups Circle (pie)- good to show a part compared to
the whole group (percentages)
1.4 Presenting Scientific Data
Scientists can communicate scientific results by writing in scientific journals or speaking at science conferences
Peer Review: is when a scientific experiment or project is reviewed by a board of scientists before getting published This shows that the project is valid