Variables8th Grade Science

Pinewood Derby

Does the mass of a derby car affect

its speed?

Scientific Question (problem):

What is being tested or

compared in an experiment.

•It is what the experiment is all about

•It is the “cause.”

•It is the “before”

What is being tested or

compared?

• Does the mass of a derby car affect its speed?

The outcome or the results

of the experiment

•What is being measured.

•It is the “effect.”

•It is the “after.”

What is being measured?

• Does the mass of a derby car affect its speed?

How to Write a Hypothesis

• Describe the relationship between the IV & DV:

–The more/less of the _IV_,

the more/less the ___DV__.

The Hypothesis should predict…

• As the IV (increases or decreased), the DV (increases or decreases).

Hypothesis•The more mass the car has, the faster it will go.

or•The less mass the car has, the faster it will go.

Constant Variables

• Stay the same throughout the experiment

Constants• Race course (distance,

steepness, etc)• Wheel size• Shape• Same kind of wood/brand• Drop time (release levers)

•Control (normal) – plain wooden car

•Experimental Group- Different weights added to car

2nd Daily Question: Write hypothesis & complete design chart

•Does the shape of the pinewood derby car, affect its speed?

• Hint: use word “aerodynamics”