Nature of Science

1. Nature of Science

2. Science is not just a subject in school but a method for studying the natural world .Science is a process that uses OBSERVATION, INVESTIGATION, MODEL BUILDING and ANALYSIS to gain knowledge about the natural world

3. Scientists need to communicate their ideas • Communication is the goal of all scientific or scholarly research.  • It encourages repeated testing and clarifying of ideas • Agreement of the scientific community is important to understanding and sharing of ideas to the public • Science is cumulative, one discovery is often made based on the work of others. If you don't know what other people have done, you have to reinvent everything yourself!.

4. Newton’s laws of Motion Einstein's Theory of relativity Drake Equation Scientific explanations help us to understand the natural world. However, explanations can change or be further defined over time as more insights and information become available. This photograph not only shows the conversion of energy to mass, but confirms Einstein's idea that a light-particle will yield up its quantum of energy all at once in a single burst.

5. Scientific Discoveries Abacus- 190 AD Use of the abacus, with its beads in a rack, was first documented in China in about 190 AD. The Chinese version was the speediest way to do sums for centuries and, in the right hands, can still outpace electronic calculators. Aspirin- 1899 Little tablets of acetylsalicylic acid have probably cured more minor ills than any other medicine. Hippocrates was the first to realize the healing power of the substance. At the turn-of-the-century, German chemist Felix Hoffman perfected the remedy. Barbed wire- 1873 The world's most divisive invention was conceived not to keep people in or out, but cows. Barcode- 1973 Barcodes were conceived as a kind of visual Morse code by a Philadelphia student in 1952. Now, black stripes have appeared on almost everything we buy. Battery- 1800 In 1780s, Italian physicist Luigi Galvani discovered that a dead frog's leg would twitch when he touched it with two pieces of metal. His friend, professor Alessandro Volta made the first battery which were voltaic cells stacked in a Voltaic pile.

6. SCIENTIFIC METHOD FOR PROBLEM SOLVING • Organized set of investigative procedures • Not always a rigid set of steps • Follows a general pattern • Not all steps are followed, some are repeated • Objective and tries not to have a bias as to what the results should be • Experiments must be repeatable • Do many trials of the experiment to ensure Validity • Sometimes a Hypothesis needs to be revised after experimentation

7. State the Problem or ask how or why something occurs Gather background information Form HYPOTHESIS or possible explanation for a problem using what you know and what you observe Test the hypothesis by performing an experiment, observing, building models, Or simulating a situation using controlled conditions Analyzing the data, record your observations in a data table Draw conclusions and decide if your hypothesis is supported or not

8. Visualizing With Models • Scientists can not see or work with everything they are investigating. A model represents an idea, event or object to small or too large to work with. Models allow people to have a better understanding of the idea.

9. Variable: a factor that can cause a change in the results of an experiment • Dependent variable: the value that changes, what you measure, the data • Independent variable: what you change in an experiment to see how it will affect the dependent variable • Constant: a factor that does not change when other variables change • Control: the standard you used to compare results

10. HYPOTHESIS • A suggested answer to a question or a problem • Usually written as : If … Then… Because • Example: If thicker paper towels soak up more water than thin paper towels, then thicker towels will absorb more water because they have more material. • The more specific the hypothesis the better you will be able to evaluate the lab • If= independent Then = Dependent

11. Technology • The application of science in our everyday lives

12. Standards of Measurement • Precision: How closely measurements are to each other and how carefully measurements were made (hit a bull’s eye) • Accuracy: compares a measurement to the real or accepted value (around a bull’s eye)

13. Metric System • Called the International System of Units or SI, “Le Systeme Internationale de Unites” used throughout the world • Base Units of Metric Measurement: • Meter -- length • Liter -- liquid volume • M3 or cm3– solid and gas volume (lxwxh) • Gram -- mass • Second -- time • Celsius-- temperature

14. 1km = 1000m 100cm = 1m 1000mm = 1m 1cm = 10mm 1cm3 =1ml Metric Prefixes

15. Practice Problems • 1000mm = ______cm = ______m • 1liter = ______ml • 450m = ______km • 77 cm = -_____m • 160 cm = _______ mm • 14 km = _______ m • 109 g = _______ kg • 250 m = _______ km