PHYSICAL SCIENCE (chapter 1) What is science? A method of studying the natural world Latin word...

PHYSICAL SCIENCE(chapter 1)• What is science? A method of studying the natural world• Latin word scientia• 3 major categories:

• Each are interconnected

The Scientific Method• An organized set of investigative procedures• 6 common steps:

State the problem• Remember, it’s not a survey

• What is the 2nd graders favorite color?• …this is not a good problem.

Research the problem• You will become an expert in your field from your

research.

Form your hypothesis• It’s not just a guess, but an informed, educated guess.• Never try to prove it correct, but rather incorrect!

Test the hypothesis• Variables – dependent (y) and independent (x)• Think of the dependent as your results.• Often, the independent is labeled as “time”.• Constants – things that don’t change in you experiment• Control – something you compare your results to

Analyze data• The best way is in a graph, chart, or table.

Line graphs, bar graph, and pie charts

• Line graphs show changes usually over time.

• Bar graphs are good for comparing data collected from counting.

• Pie charts represent a percentage.

Draw conclusions• That’s it! Your done!• Just remember…

• Avoid biases• Make sure your project is repeatable

Models represent and idea, event, or object

Theories explain, but cannot be witnessed directly

Laws are regular occurrences in nature

• Laws of Motion and Law of Gravity

Are surveys science?

• No. They are informative, but do not follow the scientific methods.

Technology – the application of science

• How has technology affected you?

Standards of measurement• “Standards” are exact quantities that never change• SI or metric system (French creation)

• Based on powers of 10• Used just about everywhere…but here!

SI prefixes and converting one into another

• kilo- hecto- deka- [unit] deci- centi- milli-

Measuring distance• Use meter sticks or rulers• SI unit is the meter (m)

Measuring Volume• cm3 and mL each appropriate labels• 1 L = 1 dm3

• Graduated cylinders and the meniscus• Read the bottom of the meniscus curve

Measuring Matter and Density• Mass is the amount of matter in an object

• The instrument for measuring is the balance.• It is measured in grams (g).

• Density equals mass/volume (g/cm3).• The label is unique. It is called a “derived unit”.

Measuring Time and Temperature• Si units for each are the second and Kelvin, though we

usually use Celsius.• Kelvin = C + 273• There are no “degrees” preceding Kelvin.