Welcome to Physical Science

Ch 1-Science skills Science vs Technology SCIENCE= system of knowledge & the methods you use to find knowledge TECHNOLOGY= the application of scientific knowledge to improve the quality of life Which came first-science or technology?

What is Physical Science? PHYSICS= study of matter & energy & the interactions between the two through forces & motion

CHEMISTRY= study of the composition (what matter is made up of), structure, properties (what matter is like & how it behaves), & reactions of matter

SCIENTIFIC THEORY versus SCIENTIFIC LAW Theory=an Explanation based on many observations supported by experimental results (explains why things work the way that they do)

SCIENTIFIC THEORY versus SCIENTIFIC LAW Law=“rule of nature” Evidence summed up by related observations & experimental results to describe a pattern found in nature.

What is the SCIENTIFIC METHOD? an organized plan for gathering, organizing, & communicating information

STEPS 1) OBSERVATION= using senses to gather info 2) PROBLEM= what do you want to know? 3) HYPOTHESIS= educated guess 4) EXPERIMENT= way to test hypothesis

STEPS in the experiment –M–Manipulated variable (Independent)= causes a change in another –R–Responding variable (Dependent)= the variable that changes in response to the manipulated variable

Controlled Experiment= a standard for comparison, hold a variable constant (does not change)

STEPS 5) ANAYLZE DATA= in words, charts, &/or graphs 6) CONCLUSION= Accept or Reject hypothesis, what you learn/discover

Analyze Data w/ Graphs Graph= a visual display of info –Pie Graphs= shows how some fixed quantities are broken down into parts *must equal 100% –Bar Graphs= show info collected by counting

Analyze Data w/ Graphs –Line Graphs= shows changes occurring over time Direct proportion= ratio of 2 variables is constant, both increase or decrease Inverse (Indirect) proportion= as one variable increases the other decreases, vice versa

Graphs

Bart believes that mice exposed to microwaves will become extra strong. He decides to perform this experiment by placing 10 mice in a microwave for 10 seconds. He compared these 10 mice to another 10 mice that had not been exposed. His test consisted of a heavy block of wood that blocked the mouse food. He found that 8 out of 10 of the microwaved mice were able to push the block away. 7 out of 10 of the non-microwaved mice were able to do the same. Identify the- 1. Control Group Mice not exposed. 2. Independent Variable Amount of microwave exposure 3. Dependent Variable Ability to move the wood block 4. What should Bart's conclusion be? Microwaves have no influence on strength of mice. 5. How could Bart's experiment be improved? Change the activity measured, more experimental groups, etc…

GUESS G= Given, identify the given information U= Unknown, identify the unknown, what are you trying to solve for? E= Equation, what equation should you use to solve the problem? S= Substitute the numbers in for the letters in the equation S= Solve, plug in the calculator, chug get an answer….don’t forget the units!