Types of variables. dependent and independent variable. control and experimental variable. scientific method or scientific enquiry.

1. The Process of Science
Sheryl Bhatnagar
University of Delhi

2. Variables
• A variable is an object, event, idea, feeling,
time period, or any other type of category you
are trying to measure. There are two types of
variables:
1. Independent
2. Dependent.

3. Independent Variable
• It is a variable that stands alone and isn't
changed by the other variables you are trying
to measure.
• For example, someone's age might be an
independent variable. Other factors (such as
what they eat, how much they go to school,
how much television they watch) aren't going
to change a person's age.

4. Dependant Variable
• It is something that depends on other factors.
• For example, a test score could be a dependent
variable because it could change depending on
several factors such as how much you studied,
how much sleep you got the night before you
took the test, or even how hungry you were
when you took it.
• Usually when you are looking for a relationship
between two things you are trying to find out
what makes the dependent variable change the
way it does.

5. Some other examples of dependent
and independent variables in
scientific experiments:
• A scientist studies the impact of a drug on cancer. The
independent variables are the administration of the
drug - the dosage and the timing. The dependent
variable is the impact the drug has on cancer.
• A scientist studies the impact of withholding affection
on rats. The independent variable is the amount of
affection. The dependent variable is the reaction of the
rats.
• A scientist studies how many days people can eat soup
until they get sick. The independent variable is the
number of days of consuming soup. The dependent
variable is the onset of illness.

6. Control Variable
• The control variable (or scientific constant)
in scientific experimentation is the experimental
element which is constant and unchanged
throughout the course of the investigation.
• The control variable strongly influences
experimental results, and it is held constant
during the experiment in order to test the relative
relationship of the dependant and independent
variables.
• The control variable itself is not of primary
interest to the experimenter.

7. Experimental Variable
• An experimental variable is something that a
scientist changes during the course of an
experiment.
• It is distinguished from a controlled variable, the
scientists keeps it constant.
• Experiments typically have many controlled
variables, but only one experimental variable.
• Experimental variables are crucial to the scientific
process; without them, the experiment is
pointless.

8. The Scientific Method
involves a series of
steps that are used
to investigate a
natural occurrence.

9. Problem/Question
Observation/Research
Formulate a Hypothesis
Experiment
Collect and Analyze Results
Conclusion
Communicate the Results

10. Steps of the
Scientific Method
1. Problem/Question: Develop a
question or problem that can be
solved through experimentation.

11. Steps of the
Scientific Method
2. Observation/Research: Make
observations and research your
topic of interest.

12. Steps of the
Scientific Method
3. Formulate a Hypothesis: Predict
a possible answer to the problem
or question.
Example: If soil temperatures rise,
then plant growth will increase.

13. Steps of the
Scientific Method
4. Experiment: Develop and follow
a procedure.
Include a detailed materials list.
The outcome must be measurable
(quantifiable).

14. Steps of the
Scientific Method
5. Collect and Analyze Results:
Modify the procedure if needed.
Confirm the results by retesting.
Include tables, graphs, and
photographs.

15. Steps of the
Scientific Method
6. Conclusion: Include a statement
that accepts or rejects the
hypothesis.
Make recommendations for further
study and possible improvements
to the procedure.

16. Steps of the
Scientific Method
7. Communicate the Results: Be
prepared to present the project
to an audience.
Expect questions from the
audience.