3. Objectives Compare and contrast independent and dependent variables. Compare and contrast experimentation and investigation. Identify the differences between mass and weight. Methods of Scientists Section 1.2

4. Review Vocabulary experiment: procedure performed in a controlled setting to test a hypothesis and collect precise data Objectives Explain what scientific notation is and how it is used. Methods of Scientists Section 1.2 Scientists use scientific methods to structure their experiments and investigations

5. The Nature of Scientific Investigations Scientists use similar methods to gather data and communicate information. Scientific methods are a series of problem- solving procedures that helps scientists conduct experiments. Methods of Scientists Section 1.2

6. The Nature of Scientific Investigations A hypothesis is a testable explanation of a situation that can be supported or disproved by careful procedures. Methods of Scientists Section 1.2

7. The Nature of Scientific Investigations A hypothesis is based on two things: Methods of Scientists Section 1.2 FACTS Your experiences

8. Visualizing Scientific Methods Scientific methods are used by scientists to help organize and plan their experiments and investigations. Methods of Scientists Section 1.2

9. Methods of Scientists Section 1.2 Please click the Diagram above to view the video. http://glencoe.com/sec/science/earthscience/2007/concept_motion/NGS/Visualizing_Scientific_Methods_1.swf

10. The Nature of Scientific Investigations Experimentation An experiment is classified as an organized procedure that involves making observations and measurements to test a hypothesis. Methods of Scientists Section 1.2

11. The independent variable in an experiment is the factor that is changed by the experimenter. A dependent variable is a factor that is affected by changes in the independent variable. The Nature of Scientific Investigations Methods of Scientists Section 1.2

12. The Nature of Scientific Investigations A control is used in an experiment to show that the results of an experiment are a result of the condition being tested. Methods of Scientists Section 1.2

13. The Nature of Scientific Investigations Investigation An investigation involves observation and collecting data but does not include a control. Methods of Scientists Section 1.2

14. The Nature of Scientific Investigations Analysis and conclusions During a scientific experiment, all data are carefully recorded. Once an experiment is complete, graphs, tables, and charts are commonly used to display data. These data are then analyzed so that a conclusion can be drawn. Methods of Scientists Section 1.2

15. The Nature of Scientific Investigations Analysis and conclusions Many times, a conclusion does not support the original hypothesis. In such a case, the hypothesis must be reevaluated and further research must be conducted. Methods of Scientists Section 1.2

16. The Nature of Scientific Investigations Scientific methods are a series of problem-solving procedures Methods of Scientists Section 1.2 Analysis the data and Investigate Make a Hypothesis Conduct Experiments… Ask a QUESTION and draw a Conclusion Repeat in necessary https://www.youtube.com/watch?v=QuKRgjm0KJU&list=PLDB484413202B3E2A&index=24 Mr. Parr Scientific Method Song

17. Measurement Le Système International d’Unités (SI) is a modern version of the metric system based on a decimal system. Length The SI unit for length is the meter (m). Methods of Scientists Section 1.2

18. Measurement Mass The amount of matter in an object is called mass. The SI unit of mass is the kilogram (kg). Methods of Scientists Section 1.2

19. Measurement Weight Weight is a measure of the gravitational force on an object. The SI unit for force is the newton (N). Methods of Scientists Section 1.2

20. Measurement Mass vs. What is the difference? Methods of Scientists Section 1.2 Weight

21. Measurement Area Methods of Scientists Section 1.2 Area is the amount of surface included within a set of boundaries. The SI unit for area is square meters (m 2 ).

22. Measurement Volume Methods of Scientists Section 1.2 Volume is the amount of space occupied by an object. The SI unit for volume is cubic meters (m 3 ).

23. Measurement Density Density is the measure of the amount of matter that occupies a given space. The SI units for density are expressed in grams per cubic centimeter (g/cm 3 ), grams per milliliter (g/mL), and kilograms per cubic meter (kg/m 3 ). Methods of Scientists Section 1.2

24. Measurement Time Time is the interval between two events. The SI unit for time is the second (s). Methods of Scientists Section 1.2

25. Measurement Temperature is a measure of the average kinetic energy of the particles that make up a material. The SI unit for temperature is the kelvin (K). Absolute zero is the coldest possible temperature. Temperature Methods of Scientists Section 1.2

26. Scientific Notation In scientific notation, a number is expressed as a value between 1 and 10 multiplied by a power of 10. Methods of Scientists Section 1.2

27. Scientific Notation Example The number of grains of sand on Earth is approximately 4,000,000,000,000,000,000,000 and would be written as: Methods of Scientists Section 1.2 4  10 21.

28. Scientific Notation Example The mass of Earth at 5,974,200,000,000,000,000,000,000 kg would be written as: Methods of Scientists Section 1.2 5.9742  10 24 kg.

29. The End of Section 1.2 Methods of Scientists Section 1.2