Chapter 1.1 Science – Learning the “rules” of the universe through observation and experimentation. A. How does science happen 1855 – Cathode rays discovered

Cathode Ray tube

A. How does science happen Chapter 1.1 Science – Learning the “rules” of the universe through observation and experimentation. A. How does science happen 1855 – Cathode rays discovered positive negative barium platinum cyanide Voltage

1. Scientist Investigate a) Collect Data Cathode rays make minerals glow. High voltage rays make glass glow.

1. Scientist Investigate a) Collect Data Cathode rays make minerals glow. High voltage rays make glass glow. Rays can pass through thin foil. Rays can only travel 2-3 cm in air.

2. Scientist Plan Experiments b. Form Question i. Can rays go through glass? 2. Scientist Plan Experiments a) What is being observed b) Exp’t set up – Cover glass with black paper

c) What will be tested “At high voltages, cathode rays will be detected outside the tube.” 3. Scientist Observe a) Record Results b) Not always what you expect -minerals glowed 1 meter away. c) New ray discovered -X-ray (1895) Wilhelm Roentgen

4. Scientist always test results a) repeat exp’t b) develop new exp’t c) rays were absorbed by dense material (Roentgen won Nobel Prize in 1901)

Wilhelm Conrad Roentgen

                                  

                       

Thomas Edison medical fluoroscope 1896

Caption: WIZARD EDISON AND EMPLOYEE INJURED BY X-RAYS AND FLUOROSCOPE, WHICH ALMOST COST DALLY'S LIFE.

B. Branches of Science Social Natural Natural Science Biological Earth Science Physical Ecology Botany Geology Physics Chemistry Meteorology Zoology

Life (Biological) botany (plants) b) Physical Science Chemistry - zoology (animals) - ecology (balance in nature) - genetics (heredity) b) Physical Science Chemistry Physics c) Combinations – biophysics, biochemistry

C. Science and Technology 1. Pure science - continue search for knowledge 2. Technology - application of knowledge 3. Science and tech. depend on each other. D. Theories and Laws 1. Theories - tested explanation a) simple and clear b) repeatable c) use to make predictions

2. Law – Statement of Observation a) Qualitative – stated in words b) Quantitative – equations of numbers (easier to communicate) 3. Theories and Laws can be replaced as we learn more.

E. Models 1. Representation of an object or event use to make study easier. 2. Examples i. picture ii. Diagram iii. Computer software Answer objectives on page 4 Answer questions 2,5,7 at end of section