scientific method

• The scientific method was developed so scientists could test possible explanations to questions, and allow others to verify the results

• The scientific method begins when a person asks a question. For example, "Do the seeds of a particular plant species need light to germinate?"

PROBLEMWhat are you trying to prove, discover, or learn about?

The question is usually followed by a thorough search for information about the topic.

Gather information about what has already been learned about the problem.

Hypothesis- a possible explanation for an observed set of facts.

Based on your research, what do you think the solution to the problem is? Sometimes, this is referred to as an educated guess.

The experiment must be done under controlled conditions. This means all factors that affect the results of the experiment (called variables) must be controlled except for the variable being studied.

experiment A carefully designed procedure used to test the hypothesis.

A collection of information and data about the experiment.

record/analyze data

This is a careful examination of the information gathered during the experiment.

Make a conclusion based on the results or data. The conclusion may support or reject the hypothesis.

conclusionWhat is the outcome of the experiment? Does the data collected prove or disprove your hypothesis?

example

1. Does vitamin C help to cure a common cold?

2. Read scientific journals and books, interview friends and family, talk to medical professionals.

3. Vitamin C does help to reduce the number of days a person suffers from the common cold.

4. To test the hypothesis, two groups of 100 cold sufferers are selected. Group A is given 1,000mg of vitamin C and group B is given a placebo (sugar pill) each day for one week beginning with the first day of cold symptoms.

5. The following data is collected:

6. Vitamin C does not have an effect on the duration of the common cold, (rejects the hypothesis)

Theories - Explanations that apply to a broad range of phenomenon and that are supported by experimental evidence.

Examples:• Big Bang Theory

• Cell Theory

• Theory of Global Climate Change

Scientific Law- a statement that describes some aspect of a phenomenon that is always true.

Examples:• Law of Gravity

• Newton's Laws of Motion

• The law of Stratigraphic Succession