August 15, 2011 Textbook Scavenger Hunt Find a partner and a textbook Grab a Scavenger Hunt worksheet from table Answer questions using book Turn into tray when you are finished

Introduction to Physical Science Notes 1.1

Unit Objectives Identify the steps scientists often use to solve problems. Describe why scientists use variables. Distinguish between dependent and independent variables. Distinguish between precision and accuracy with respect to experimental data. Name the prefixes used in SI and indicate what multiples of ten each one represents. Identify units and symbols for various measurements made in science. Identify three types of graphs and explain the ways they are used. Analyze data using the various types of graphs. Compare and contrast science and technology.

What is Science? Comes from the Latin "scientia," meaning knowledge. Method of studying the natural world "knowledge attained through study or practice," or "knowledge covering general truths of the operation of general laws, esp. as obtained and tested through scientific method [and] concerned with the physical world." http://www.sciencemadesimple.com/science-definition.html

Science Social Natural Life Science Biology Earth Science Astronomy Geology Physical Science Physics Chemistry

Branches of Science Three MAIN BRANCHES Life science deals with living things. Earth science investigates Earth and space. Physical science deals with matter and energy.

In-Class Assignment/Homework Tree of Science Activity

Lab Safety Video

Notes 1.1 continued The Scientific Method

Scientific Method Organized set of investigation procedures

Components of Experiment Hypothesis = possible explanation for a problem using what you know and observe Experiment = tests one thing in a controlled environment

Components of Experiment Variable = factor that can cause a change in the results of an experiment Dependent = variable changes according to how the experiment is set-up Independent = variable you change in the experiment Control = factor that does not change when other variables do

Laws vs. Theory Theory = explanation of things or events based on knowledge gained from many observations & investigations Hypothesis becomes a theory after many investigations Theories can be accepted one day and discarded another

Law vs. Theory Law = statement about what happens in nature and seems to be true all the time Tells what will happen under certain conditions but doesn’t explain why or how something happens Theory can be used to explain a law

In-Class Assignment/Homework Scientific Method Reinforcement WKT

Variables Modified from a PowerPoint created by www.physics4u.co.uk This sequence of slides is designed to introduce, and explain the different kinds of variables, as explained on pages 7 and 360 in New Physics for You, 2006 & 2011 editions.

Variables are things that vary and change

In any experiment there are 3 variables: An independent variable A dependent variable Some control variables

Independent variable This is the thing that you decide to change. Example 1 Investigating how a weight affects the length of an elastic band. You decide the weight to apply, so: Weight is the independent variable.

Example 2 initial temperature is the independent variable. Investigating how the rate of cooling of a beaker depends on the initial temperature. You decide the initial temperature, so: initial temperature is the independent variable.

Dependent variable This is the variable that changes as a result. It is the variable that you measure. Example 1 Investigating how a weight affects the length of an elastic band. You measure the resulting length of the elastic band, so: Length is the dependent variable.

Example 2 temperature is the dependent variable. Investigating how the rate of cooling of a beaker depends on the initial temperature. You measure the temperature every minute as it cools, so: temperature is the dependent variable.

Control These are all the variables that must not change, to make sure it is a fair test. Example 1 Investigating how a weight affects the length of an elastic band. You must use the same elastic band all the time, and the same scale etc, so it is a fair test.

Example 2 Investigating how the rate of cooling of a beaker depends on the initial temperature. You must use the same beaker, with the same amount of water, in the same position in the room, at the same room temperature, so it is a fair test.

Summary – Example 1 weight length of the elastic The independent variable is ? weight The dependent variable is ? length of the elastic The control variables are ? same elastic band, same scale, etc, so it is a fair test.

Summary – Example 2 initial temperature temperature as it cools The independent variable is ? initial temperature The dependent variable is ? temperature as it cools The control variables are ? the same beaker, with the same amount of water, in the same position in the room, at the same room temperature, so it is a fair test.