Unit 1: The Nature of Science

What is science?

• Science is a way or a process used to investigate what is happening around you.

• It can provide possible answers to your questions.

How can the problem be solved?

• Two methods used to answer questions are descriptive research and experimental research design.

• Descriptive research answers scientific questions through observation (using your senses).

• Experimental research design is used to answer scientific questions using the scientific method.

What is the scientific method?

• Scientific methods are ways, or steps to follow to try to solve problems. Different problems will require different methods to solve them.

Scientific Method Steps

• Recognize the problem – What is the question you want answered?

• Form a hypothesis – Make a prediction or a statement that you can test.

• Test your hypothesis – Perform an experiment to check the accuracy of your hypothesis

• Analyze your data – Look at the information carefully that you have collected from experiment.

• Draw Conclusion – State whether your hypothesis matches your results.

• Communicate your results – Publish in lab report, science journal, science project, etc.

Experimental Research Design• In well planned experiments, one factor, or variable,

is changed at a time.

• The variable that is changed is called the independent variable.

• A dependent variable is the factor being observed.

• The variables that stay the same are called constants.

• A control group is a sample that is treated like the experimental group(s) except that the independent variable is NOT applied.

• An experimental group HAS an independent variable in the experiment.

• Independent and Dependent Variable Plant Sheet

How does soap affect surface tension?

Constant Control Group Experimental Group

Dependent

Variable

Independent Variable

Variables that stays the same

Sample treated like experimental group

but independent variable is NOT

applied

Independent variable IS

applied

Factor Being

Observed (Measure

d)

Variable that is

changed (added)

How does soap affect surface tension?

Constant Control Group Experimental Group

Dependent

Variable

Independent Variable

Variables that stays the same

Sample treated like experimental group

but independent variable is NOT

applied

Independent variable IS

applied

Factor Being

Observed (Measure

d)

Variable that is

changed (added)