Scientists use experiments to test a hypothesis hypothesis or answer a question question

• Variables are factors or parts that can change during an experiment

Manipulated (independent) Manipulated (independent) variablevariable: : • what you change on purposepurpose• There is onlyonly ONE MV in an experiment

RespondingResponding (dependent) variable:

What you are measuringmeasuring.

Controlled variables: Controlled variables:

What you keep the same (also called constantsconstants.)

Parts of an Experiment

QUESTION/PROBLEMWhat question is being answered, problem solved, or hypothesis tested. What is the purpose of doing the experiment?

What is the effect of MV on RV?How does MV affect RV?

HypothesisHypothesisAn educated guess or a prediction about the results.

• If (the manipulated variable does this), • then (the responding variable) will (describe

what will happen)• because (give a reason for your prediction)

Parts of an Experiment

Materials:Items used during the experiment.

• Write in a bulleted list.• Include details – how much you will

need, units of measurement, sizes

Parts of an Experiment

ProceduresProcedures:Steps followed during experiment.

– Write in a numbered list– Should be detailed enough that anyone can

follow exactly what you did.– Always say to “Record Data”– Always say how many times the experiment

will be repeated (4 total trials)

Parts of an Experiment

Observations/Data:Observations/Data:

All the information gathered whileperforming the experiment.• Should include written

observations AND a data table

Parts of an Experiment

Results/Conclusions:Results/Conclusions:Analyze your data to determine the final outcome of the experiment. What do you NOW believe as a result of the experiment or observations?

Parts of an Experiment

Results/Conclusions:Results/Conclusions:

1. 1. Make a Graph• Decide on the kind of graph: Time

progression = line, Objects = bar• Set up your axis range• Label your axes (x=MV, y=RV)• Title your graph

Parts of an Experiment

Results/Conclusions:Results/Conclusions:

2. 2. Write a conclusion paragraph • Restate your hypothesis and relate your findings

to it (correct or incorrect)• Support your claim with at least 2 pieces of data

– use numbers from your data table!• Explain why/how your data supports your answer

Parts of an Experiment

Share your results:Share your results:

Publish your findings so that others may benefit from your work.

Parts of an Experiment