What is Science? PHYSICAL SCIENCE DR. CARPENTER

What is science?  A way of learning more about the natural world  Scientists want to know why, how, or when something occurred  Asking questions  Can change answers with new information from new or repeated tests

Theory vs Law TheoryAlikeLaw Attempt to explain a natural event MUST be supported by observations and results in many investigations Describes a pattern in nature Best explanations based on current information Can change with new information Helps make predictions Tries to explain whyDoes not explain why

Examples  Theory  Big Bang  Creationism  Evolution  Why the Sun rises every day  Law  Gravity  Motion  Where the Sun rises every day

BrainPop Scientific method  d/preview.weml d/preview.weml  Take quiz and show Dr. Carpenter your score

Science and Technology  Different branches of science  Physical science is the study of energy and matter  Technology is the practical use of science – science application  Examples:  Pencil    

Scientific Method  A series of steps used to solve a problem or answer a question.  1 st – What’s the problem?  2 nd – Gather information  3 rd – Hypothesis  4 th – Experiment/ evaluate  5 th – Data collection  6 th – Evaluate data and make a conclusion  Repeat (ALL valid experiments must be repeatable.)

Experiments  Controlled experiment involves changing 1 factor and observing its effects on another factor while everything else stays the same.  Variables – those factors that can be change  Independent (experimental or manipulated) variable – The factor that you change  Dependent (responding) variable – what happened because you made the changes  Constants – never changes

Lab safety  #1 rule – FOLLOW teacher's directions  Never eat out of or off of ANY lab equipment.  Inform the teacher ASAP of any accidents.  Others:      

Models  ANY representation of an object or an event  Types:  Physical – those you can see and touch  Computer – those you can see on a computer  Idea – equations or another representation  Useful to communicate ideas and thoughts  Limited because ideas and concepts change – like the solar system and the atom

Evaluating scientific explanations  Critical thinking – combining what you know with new facts to see if you agree with it  Data – recorded observations from an experiment  Is it specific?  Can the data be repeated?  Evaluating the conclusion:  Bias -- when the research influences the results either by not thinking of ALL variables OR choosing subjects they know will answer a certain way  EX – Nike testing shoes and finds Nike shoes are the best.  Nintendo testing how useful their machine is fighting childhood obesity  Using Japanese students’ test scores to indicate how much better they are that US students (not all children are educated in Japan)

Measurement  Way to describe the experiment with numbers  Estimation can help make a rough measurement  Precision  How close to each other are measurements  Getting the same, or almost the same, measurement every time  Accuracy  How close to the real or accepted value is something  Getting a basketball to go through the net every time is accurate  The more points behind the decimal point in a problem, the more accurate the answer

BrainPop  BrainPop __ Precision and Accuracy  ccuracy/preview.weml ccuracy/preview.weml  Take the quiz and show Dr. Carpenter your score

SI Units  SI stands for “System Internationale” (International System)  Standard unit used by scientists  All units based on 10s  We call it the metric system

SI units  Length – meter (m)  Volume – either  cubic centimeter (cm 3 )  milliliter (ml)  Mass – kilogram (kg)  Weight – Newton (N)  Temperature – Kelvin (K)  Time – second (s)

BrainPop SI units  view.weml view.weml  Take quiz and let Dr. Carpenter see your quiz grade

Graphs and tables  Table —  Shows data in rows and columns  Graph –  Line graph – shows relationship between 2 variables (shows change over time)