CHAPTER 1 “The Nature of Science” Mrs. Nell’s Physical Science Class

Science Is Everywhere Science in the movies… Chemical reactions Mechanics Hydraulics Electronics Acoustics Still images appear to move (human eye blends images)

Pure Science vs. Applied Science Pure science is the gathering of new information. Applied science (or technology) is using knowledge gained from pure science to solve problems.

Three Major Categories of Science Life science: study of living organisms Earth science: study of Earth and space Physical science: study of matter and energy (chemistry/physics)

Problem vs. Exercise A problem in science is a situation when some information appears to be missing. An exercise is when the steps to find the solution are obvious.

Model A model is an idea or structure that represents what you’re trying to explain. This is a DNA model and a model of an atom.

Scientific Method The scientific method is a set of procedures used by scientists to search for solutions to problems. Steps of the Scientific Method: 1.Question 2.Observations 3.Hypothesis 4.Experiment 5.Collect Data 6.Conclusion

Theories and Laws Theory: explanation based on many observations supported by experimental results Scientific Law: rule that sums up related observations and experimental results to describe a pattern in nature (ex.- Law of Gravity) Information gathered from experimentation is used to form a theory or state scientific laws.

Science of Special Effects Special EffectIn the PastToday RocksMade of paper mache Made of polyurethane foam or fiberglass; more realistic and lightweight GlassMade from hardened sugar water; melted under bright lights or when wet Made of plastic; shatters easy without hurting stunt men Computers- - -Animations, special effects done with go- motion- makes effect smooth- more realistic

Independent and Dependent Variable An independent variable is the factor adjusted by the experimenter. (In the popcorn example when we looked at whether storing popcorn in the freezer makes it pop better… the independent variable was the temperature). The dependent variable is the factor whose value depends on the value of the independent variable (in the example above the dependent variable is the number of un-popped kernels).

The Control & Constants The control in an experiment is the standard for comparison (in the example above we would have to store some popcorn at room temperature so we could compare our results- the popcorn at room temp is the control). Any conditions that are the same are our constants (we’d need to use the same brand, same freshness, same storage time,… these are constants).

Problem Solving Strategies 1. Look for patterns… ecentral/tracker 2. Develop a model…

3. Break it down into smaller, simpler problems…

Critical thinking is a process that uses certain science skills to solve a problem. Example- apply your critical thinking skills in analyzing the following situation… Sponge Bob notices that his pal Gary is suffering from slimotosis, which occurs when the shell develops a nasty slime and gives off a horrible odor. His friend Patrick tells him that rubbing seaweed on the shell is the perfect cure, while Sandy says that drinking Dr. Kelp will be a better cure. Sponge Bob decides to test this cure by rubbing Gary with seaweed for 1 week and having him drink Dr. Kelp. After a week of treatment, the slime is gone and Gary’s shell smells better. What was the initial observation? What is the independent variable? What is the dependent variable? What should Sponge Bob’s conclusion be?

Muscle Cream Larry was told that a certain muscle cream was the best thing on the market and claims to double a person’s muscle power when used as part of a muscle-building workout. He buys the special muscle cream and recruits Patrick and SpongeBob to help him with an experiment. Larry develops a marshmallow weight-lifting program for Patrick and SpongeBob. He meets with them once a day for a period of 2 weeks and keeps track of their results. Before each session Patrick’s arms and back are lathered in the muscle cream, while Sponge Bob’s arms and back are lathered with the regular lotion. Which person is the control group? What is the independent variable? What is the dependent variable? What should Larry’s conclusion be? TimePatrickSpongeBob Initial amount 185 After 1 week 249 After 2 weeks 3317

Observation vs. Inference 1. John is big and tall. 2. It is cloudy outside, it is probably going to rain. 3. She must be intelligent, because she wears glasses. 4. It is warm in this classroom. 5. It is cold so it will probably snow tonight.

Observation vs. Conclusion 1.The mixture is sugar and salt. 2.The liquid is green. 3.The substance is cold. 4.Aluminum conducts electricity. 5.It is going to snow. 6.It flows like a liquid. 7.The eighth grade is loud. 8.The liquid is ethyl alcohol. 9.The box is heavy.