THE SCIENTIFIC METHOD

WHAT IS THE SCIENTIFIC METHOD?

Steps taken in a specific order to get an answer to a posed problem

Steps include: Observation State the Problem Research Hypothesis Experiment Results Conclusion

WHY DO WE USE THE SCIENTIFIC METHOD?

To organize experiments so others can repeat it and validate it

To communicate results effectively

OBSERVATION

Process of gathering information about events or processes in a careful, orderly way

Scientists collect data and use data to form inferences

Inference – a logical interpretation based on prior knowledge or experience

PROBLEM

Something you are trying to solve

The question that is being asked

Must be testable with measurable results

Example: Are the boys or girls in this class taller?

HYPOTHESIS

Prediction based on inference from observation

Testable solution to a question or problem

Can be written as an IF/THEN statement

If I get out of my seat and dance around the room, I will get in trouble with the teacher.

The sky is Blue.

Because there is a football next to the broken window, someone playing football must have broken my window.

It must have rained because there are many puddles outside.

The car is moving at 45 mph.

If I touch the hot handle on the pan, then I will likely burn my hand.

If the Heritage football team practices real hard all week, then they will win the next football game.

Wow! It really smells funny in here today.

Fall must be on its way because I am already back in school.

The bird likes to fly.

The tree by the pond is dead.

The drink is a Pepsi.

EXPERIMENT

Way of testing your hypothesis Setup of lab should be clear enough

that anyone would be able to follow the steps to do the experiment

Often requires collaboration – Scientists working together or

building upon each others work

EXPERIMENT TERMINOLOGY

Independent Variable: the thing in the experiment that you change (manipulate)

Dependent Variable: The thing that is observed and changes in response to the independent variable

Controlled Variable: The things that you do NOT change (you are not testing the impact of these)

Controlled Experiment: Experiments in which only one variable at a time is changed

Famous experiments discrediting theory of spontaneous generation

late1700s

1862

1668

RESULTS

Data collected during an experiment Can be in the form of a chart or graph Can be in the form of illustrations or

observations Quantitative – measureable data Qualitative – observable data

CONCLUSION

Hypothesis is supported or refuted (we NEVER prove or disprove)

Explains how the experiment can be applied to real life

Future Experiments Identifies any sources of error – How can the

experiment be improved if we did it again?

SCIENTIFIC THEORY

A general statement of why things work based on hypotheses that have been tested many times

Theories are used to explain and predict the outcome of other experiments

Sometimes they are wrong and must be modified or discarded

SCIENTIFIC LAW

A statement of what happens in a certain event based on verified observations and experiments

A basic scientific theory that is no longer tested and is generally accepted as true (Newton’s Law of Gravity)