9 th Grade Science Chapter 1 AB Goals

9 th Grade Science Chapter 1 A-B

Goals • Identify the steps scientists use to solve problems • Define and understand the use of variables

Scientific Method • Basic Steps: – Formulate a question – Collect information – Make an hypothesis – Test the hypothesis – Draw a conclusion (about the hypothesis) – Report! • Why do we use it? • Song

Testing! • All science is testable! • Test may be: – More observation – Experiment with control • Control: a group that does not have the experimental factor changed • Variables measured: – Independent variable: • One thing we change! – Dependent variable: • What we measure: what changes as a result of the independent variable • Repeated testing leads to theories and laws

Theories and Laws • Scientific Theory: – Explains how or why a natural event occurs – Usually incorporates many supported hypotheses and is developed to explain them – Example: • Scientific Law: – Describes something that occurs naturally and seems to occur in the same way all the time – Does NOT explain how/why – Example:

Goals • Name and define common prefixes used in the metric system • Identify SI units for length, volume, mass, time and temperature • Convert from one SI unit to another

How do we measure? • Metric system standard measurements – AKA System Internationale (SI) • Length: – Meter • Mass: – Gram • Temperature: – Celsius degree • Time: – Second • Volume: – Liter

Conversion! • Mr. Boal’s Handy Dandy Conversion Line!

Conversion Examples • You have a length of rope that measures 3075 mm. How long is it in: – Centimeters – Meters – Kilometers • Your pencil has a mass of 7. 5 g. What is its mass in: – Kilograms – Centigrams

• Practice Problem p 16! Your pencil is 11 cm long. How long is it in mm?

• Convert 15. 6 m. L to L • Convert 25. 4 kg to mg

• Volume of a solid • Density: – Amount of mass per volume