HOW SCIENTISTS ANSWER QUESTIONS! Scientific Inquiry
The many ways that scientists study the natural world and propose explanations based on the evidence they gather
Steps of Inquiry Step One: Ask a question Question must be testable Does not involve personal opinions Example: Why do flowers have bright colors?
Which of these questions can be answered by inquiry? Is football a better sport then baseball? Does running make your muscles stronger then swimming? Which brand of running shoes look the best? Come up with your own “testable” question. It can be about ANYTHING.
Step two: Developing a hypothesis A possible answer for the question being asked Based on your prior knowledge and predictions Must be testable! Can you do an experiment to find out if you are right or wrong? A hypothesis should be tested many times before it is accepted as true or false
How to write a hypothesis Sometimes it is written as an “If/Then” statement Not always possible to write it this way! Question: Are students more active after eating lunch? I think that if students eat lunch, then they will be more active Can we test this hypothesis?
Practice: Does drinking coffee as a teenager make you shorter? Hypothesis:
Step Three: Designing an experiment HOW will you test your hypothesis? Develop a PROCEDURE The steps you follow to test your hypothesis and answer the question How am I going to answer the question? Must be detailed and specific
Things to know when writing a procedure Variable: Something you change or manipulate during an experiment Example: You are trying to find out if a pond plant grows best in clean or dirty water Variable: clean or dirty water
In order to have a successful experiment you must CONTROL the variables that are NOT being tested Keep other variables the same throughout the whole experiment Example: water temperature, where the water comes from, type of pond plant must be the same for the whole experiment.
Two types of variables: Manipulated variable :the thing that is purposely changed in an experiment Clean or dirty water Responding variable: The thing that may change in response to the manipulated variable How well the pond plant grows
Controlled Experiment Only ONE variable should be tested at a time Testing more then one variable at a time can confuse the results You can’t test whether pond plants grow better in clean or dirty water AND whether they like warm or cold water Variables that you keep the same for the experiment are called controlled variables
Practice Question: Do worms survive better in wet or dry soil? Variables: Manipulated: Responding: Other variables to control:
Step Four: Results The data you collect after performing the experiment Numbers (quantitative observations) Descriptions (qualitative observations) Usually organized into a data table and/or graph
Analyze Results/Conclusion Interpret your results. Must be based on the results from your experiment only States whether your hypothesis was correct and any further testing that needs to be done
Share and Repeat Scientist must share their results with the scientific community Repeat – in order to prove a hypothesis you must repeat the same experiment many times.
Types of Experiments Statistical experiments Controlled/laboratory experiments Field experiments