Ch. 1, Section 1 – The Nature of ScienceI. Problem Solving

A. Problems vs. Exercises

1. Problem: A question about something that has no easy or obvious answer.

Ozone Hole Animation

2. Exercise: A question that has obvious steps to find answer.

B. Ways to Solve Problems…

1. Predict solutions and try them (retrace steps)

2. Look for patterns and make predictions (always late for class)

3. develop a model – an idea, system, or structure that representsthe problem.(planes in wind tunnels)

4. Break down the problemintosmaller

problems.(saving the earth)

[The 16-foot wind tunnel at Ames Research Center]

C. Scientific Problem Solving1. There are certain steps to solving problems in science (scientific method)

a. State the problem: observe something in natureand ask “why?” (observation-use senses to gather information)

b. Hypothesis: predictions that can be tested

c. Experiment: testing predictions made (analyze results)

d. theory: making an explanation based on observations(draw conclusions)

e. scientific law: “rule of nature” proven many times tobe true

HMMMMM...

Scientific Method

3. Experimentationa. Experiment: Organized procedure for testing a hypothesis

b. What is needed to perform experiments:

1. Control: A standard for comparison

2. Constants: Unchanging factors

3. Variables: changing factors

a. Independent Variable: adjusted in experiment (x)

b. Dependent Variable: depends on value of independent (y)

II. Graphing

A. Bar Graphs: Used for comparing objects (like hair colors)

B. Circle (Pie) Graphs: Used to represent parts of a whole (percents)

C. Line Graphs: Used to show trends or changes over time (stocks)

B. Metric System: System of measurement based on multiples of 10; used worldwide; uses prefixes when converting

[kilo-(k) hecto-(h) deka-(dk) BASE- deci-(d) centi-(c) milli-(m)]

B-d, B-d, B-d, That’s All Folks!!

III. Standards of measurementA. Standard—an exact quantity that people agree to use for comparison.

C. In science, we now use an improved version of the metric system called “International System of Units” or SI units.

--SI comes from the French Le Systeme Internationale d’Unites

Measurement Definition U.S. unit SI UnitLength Distance between two points ft m

Mass The “stuff” that makes up an object kg kg

Volume Amount of space an object takes up ft 3, in3 L, cm3

Time Interval between two events sec s

Density Amount of mass in certain volume lb/ft 3 kg/L

Temperature How “hot or cold” and object is ˚F, ˚C K