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 Method 4. 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-Aid Dependent 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 happened 6. 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 X X 10 5

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 = cm 3 Liquids = mL

Open book to page 16 Base units (Page 16) Derived Units (Page 16)

Density: mass per unit of volume  D=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