The Nature of Science

1. The Nature of Science Chapter 1 Chapter 1

2. Earth Science Section 1.1

4. Objectives Differentiate among the four major branches of Earth Science Contrast the four systems of Earth Discuss how Earth Science affects your daily life

5. astronomy The study of objects beyond Earth’s atmosphere

6. meteorology The study of air or atmosphere and the processes that produce weather and climate

7. geology The study of the materials that make up earth and the processes that form and change these materials Geologists study rocks

8. oceanography Study of Earth’s oceans, including seafloor movement, marine life and topography

9. Dam Picture!

10. Earth’s Systems Scientists have identified four main Earth systems: Lithosphere Hydrosphere Atmosphere Biosphere

11. Lithosphere The lithosphere is the rigid outer shell of the planet that includes the crust and mantle Two kinds of crust: oceanic and continental Continental is mostly granite and oceanic mostly basalt

12. Lithosphere Mantle: Located between the crust and core of the Earth Crust: Thin outside layer of the Earth’s surface

13. Lithosphere • The upper mantle is mostly rigid rock, but some is partially molten • Partially molten mantle is asthenosphere • Below the mantle is the core • The core can be divided to: • Outer liquid part and inner solid part

14. Hydrosphere All water on Earth Oceans account for 97% of all Earth’s water 3% is freshwater (groundwater, streams, lakes, and glaciers) ¾ freshwater in glaciers and icebergs

15. Atmosphere The blanket of gases surrounding our planet Protects us from sun’s heat and dangerous radiation 78% nitrogen, 21% oxygen

16. Biosphere All organisms on Earth and the environments they live in

17. Earth’s Systems • The biosphere, lithosphere, hydrosphere, and atmosphere are interdependent systems • They depend on each other!

18. Methods of Scientists Section 1.2

19. Objectives List steps used in a scientific method Compare and contrast experimental variables and controls Identify basic SI units Explain how to write numbers using scientific notation

20. Nature of Scientific Investigations A scientific method is a planned, organized approach to solving a problem The first step is identifying the problem Research the problem then develop a hypothesis A hypothesis is a suggested explanation for an observation

21. Experimentation A hypothesis is tested by an experiment An experiment is an organized procedure that makes observations and measurements Good experiments test one variable, or changeable factor at a time

22. Experimentation The independent variable in an experiment is manipulated by the experimenter A dependent variable in an experiment is a factor that can change if the independent variable changes (what is being measured) A control is used a factor that does not change to prove that results are actually a result of a condition tested

24. Measurement Most scientific studies use a standard system of units, Le Systeme International d’Unites, or SI SI is a decimal system that uses 10 as the base unit

25. Length Standard SI unit for length is meter (m) 1 m is divided into 100 parts called centimeters (cm) 1 millimeter (mm)is smaller than a cm, with 10 mm in 1 cm

26. Weight and Mass Weight is the gravitational force of an object Weight is a force so the SI unit for force is Newton (N) Mass is the kilogram (kg) Mass is the amount of matter in an object which depends on the atomic makeup

28. Area and Volume • Area requires a combo of SI units and is the surface area of an object in given boundaries • LxW • Volume is the amount space occupied by an object • LxWxH • Solid volume (m³), liquid volume (cm³=1 mL)

29. Density and Time Density is the measure of the amount of matter that occupies a space m/v Time is the interval between two events SI unit is Seconds (S)

30. Scientific Notation In science, some numbers are very small while others are very large Scientists have a type of shorthand called scientific notation to express the number as a multiplier and power of 10

31. Scientific Notation A number is expressed as a value between 1 and 10 and multiplied by a power of 10 The power of 10 is the number of places the decimal point must be shifted so that only a single digit remains 90,000,000= 9x 10⁷

32. Theory and Law A theory is an explanation based on many observations during repeated experiments It is only valid if it is consistent with observations, predictions and explanations A law is a principle that describes the behavior of a natural phenomenon Aka: rule of nature The events described by a law are the same each time