Chapter 2 Measurements and Calculations

2-1 Scientific Method The scientific method is a logical approach to solving problems by observing and collecting data, formulating hypotheses, and formulating theories that are supported by data - Davis, 2004 p. 29

Observing Observing is the use of the senses to obtain information. Involves making measurements and collecting data. - Davis, 2004 p. 29

Data Data can be qualitative (descriptive) The sky is blue His shirt is red with stripes It is warm outside Data can be quantitative (numerical) The temperature is 82°F The car is moving at 65 mph

Systems A system is a specific portion of matter in a given region of space that has been selected for study during an experiment or observation.

Observations  Hypothesis We use the generalizations formed from our observations to formulate a hypothesis – a testable statement. This serves as a basis for making predictions or carrying out further experiments.

Formulating Hypotheses Scientists attempt to derive the simplest possible explanation that accounts for the data… KISS

Support/Refute Hypothesis Confirmation of hypotheses by data strengthens their validity. Repeated and widespread inconsistency of data with a hypothesis leads to a rejection of that hypothesis.

Hypothesis Why can’t we PROVE a hypothesis? Impossible to test/account for every single factor or possible combination Data that supports a hypothesis strengthens its validity

Successful Hypotheses When data shows that the hypothesis is successful at predicting results, scientists construct models to explain the phenomena they are studying

Model A model in science is an explanation of how phenomena occur and how data or events are related. Visual, verbal, mathematical, physical

Theory A model that successfully explains many phenomena may become part of a theory. A theory is a broad generalization that explains a body of facts or phenomena and can predict the results of new experiments or observations.

Law General statements that describe how the natural world behaves under certain conditions. Generally presented as a mathematical statement

Scientific Method Observing Questioning Formulating a hypothesis Testing a hypothesis Theorizing/Model making Publishing Results Not a Linear process!!

Solve the Problem… The game is in the name of the game – polar bears around an ice hole – invented in the days of Genghis Khan. A clue for you to keep you true – like petals around a rose, you can count each bear’s nose. How many polar bears do you see?

Homework Pg.31 #1-5