1. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Scientific Methods Chapter 1 What You Will Learn Scientific methods are based on six steps, which may be followed in different ways based on the kind of question being asked. Scientific investigations begin with a question and proceed by forming a hypothesis and then testing it. Scientists use a variety of methods to analyze and report their data.

2. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Scientific Methods Chapter 1 What Are Scientific Methods? Scientific methods are a series of steps followed to solve problems. The six steps used in scientific methods are asking a question, forming a hypothesis, testing the hypothesis, analyzing the results, drawing conclusions, and communicating results.

3. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Scientific Methods Chapter 1 What Are Scientific Methods?, continued Scientists may use all of the steps or some of the steps during an investigation. They may even repeat some of the steps or do the steps in a different order. How scientists choose to use the steps depends on what works best to answer their question.

4. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu The Nature of Physical Science Chapter 1

5. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu The Nature of Physical Science Chapter 1 Scientific Methods

6. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Scientific Methods Chapter 1 Asking a Question Asking a question is often the first step in using scientific methods. Asking a question usually results from making many observations.

7. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Scientific Methods Chapter 1 Asking a Question, continued Observation is the process of obtaining information by using the senses. Asking a question helps scientists focus the purpose of an investigation.

8. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Scientific Methods Chapter 1 Forming a Hypothesis After scientists ask a question, their next step is usually to form a hypothesis. A hypothesis is a possible explanation or answer to a question. A good hypothesis is a testable idea that leads to scientific investigation.

9. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu The Nature of Physical Science Chapter 1 Hypothesis

10. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Scientific Methods Chapter 1 Testing the Hypothesis After scientists form a hypothesis, they usually test the hypothesis to find out if it is a reasonable answer to their question. A controlled experiment compares the results from a control group with the results from experimental groups. A controlled experiment is a good way to test a hypothesis.

11. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Scientific Methods Chapter 1 Testing the Hypothesis, continued The factors that are kept the same between the groups are called controlled parameters. The one factor that changes between the groups is called a variable parameter. Data are any pieces of information acquired through observation or experimentation.

12. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Scientific Methods Chapter 1 Analyzing the Results After scientists test a hypothesis by performing an experiment, they usually analyze their results. Analyzing results by using tables and graphs helps scientists understand relationships between the data.

13. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Scientific Methods Chapter 1 Analyzing the Results, continued Analyzing data from repeated tests can help scientists determine if their data are accurate and reproducible. Data are reproducible when you get similar data from many tests.

14. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu The Nature of Physical Science Chapter 1

15. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Scientific Methods Chapter 1 Drawing Conclusions After scientists analyze their results, they usually draw conclusions about whether their hypothesis was supported. Valid conclusions can only be obtained with reproducible data.

16. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Scientific Methods Chapter 1 Drawing Conclusions, continued Data are considered reproducible when scientists get similar data from many repeated tests. Reproducible data helps scientists make sure that the results of their experiment were not an accident.

17. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Scientific Methods Chapter 1 Communicating Results After drawing conclusions, scientists often communicate their results. When scientists communicate their results, it allows others to continue the investigation. Results can be communicated through scientific papers, presentations, and the Internet.