6.1 Scientific Investigation

Mr. S. sets up an experiment to see how the mass of a ball affects the distance it rolls off a ramp.  Identify the independent variable.

• distance traveled by the ball
• height of the ramp
• mass of the ball
• weight of the ball

How many variables can be tested in a controlled experiment?

• one
• two
• three
• as many as possible

The independent variable is the ONE thing you _____.

• change
• keep the same
• experiment with
• investigate

What step does every scientific experiment begin with?

• hypothesis
• question/problem
• procedures
• conclusion

Why do we want to test one variable at a time?

• Because it is hard to setup a data table with more
• To know what is causing the changes
• It is what has always been done
• No one really knows

An experiment is performed on plants to see how different liquids affect plant growth. Each plant in the experiment is given a different liquid; water, apple juice, or milk. Each plant has the same amount of soil, sunlight, and listens to the same music. In this investigation, what is the dependent variable?

• Type of plant
• Water, apple juice, milk
• Plant growth

Which variable stays the same for each test  in an experiment?

• Dependent
• Independent
• Control

Two types of observations scientists collect are...

• hypothesis and theory
• qualitative and quantitative
• myths and fables
• metric and standard measurements

You want to collect information on the taste of apples to help a farmer grow sweeter apples in his orchard.  You have your assistants describe apples as "sweet" or "tart".   This is called ____ observations

• quantitative
• qualitative
• not scientific
• hypothetical

Measuring the number of times a person breathes after exercise involves ____ observations. 

• quantitative
• qualitative