MS Physical Science 1.2: Types of Investigations

Types of Investigations

by Mrs. Ojerio

​Descriptive Investigations

• ​Looking at objects, events, and systems and collecting data about them.​

• ​Tools such as magnifying lenses and cameras help you reveal and collect the details

​Comparative Investigations

• ​Looking for ways that two or more objects, events, or processes are alike and different.

• ​Involves using data to form conclusions.

​Experimental Investigations

• ​Looking for patterns in data by using an experiment.

• ​Most common type of investigation.

Multiple Choice

Which of the following is an example of a descriptive investigation?

• Determining the number of each type of bird in a park.

• Determining how two rock samples are alike and different.

• Determining which type of battery will last longer in a flashlight.

Multiple Choice

Which of the following is an example of a comparative investigation?

• Determining the number of each type of bird in a park.

• Determining how two rock samples are alike and different.

• Determining which type of battery will last longer in a flashlight.

Multiple Choice

Which step in a comparative investigation is not included in a descriptive investigation?

• Ask questions

• Compare

• Make observations

• Collect data

​Hypothesis

• ​Similar to a guess, but must be something that can be tested.

• ​Often an "if-then" statement.

​Variables

• Manipulated: What you are changing.

• Responding: what you are measuring.

• Constant (sometimes called Controlled): what is staying the same.​

​Controls

• ​Serves as a baseline for comparison.

• ​Usually does not experience the manipulated variable (what is changing).

​Trials and Replication

• ​Experiments should include several different sets of conditions (or subjects).

• ​Each set of condition would be a Trial.

• ​Experiments should be repeated several times to make sure results are valid.

• ​Repeating an entire experiment would be a Replication.

​Practice Scenario

​Uh oh...you've dripped ketchup all over your favorite white cotton shirt.

​

Your mom tells you an old-fashioned trick: Pouring white vinegar on a stain will work better than laundry detergent to remove it.

Is that true? You'll need to design a controlled experiment to find out!

Multiple Choice

Select the best hypothesis to use for your experiment:

• If I use vinegar on one ketchup stain and laundry detergent on another, the vinegar will remove more of the stain.

• Vinegar is good at removing ketchup stains.

• I think vinegar smells really bad.

• Should I use vinegar or laundry detergent to remove a ketchup stain?

Multiple Choice

The manipulated variable is:

• the type of ketchup

• the substance that is added to the stain

• the color of the stain afterward

Multiple Choice

The responding variable is:

• the type of fabric

• the substance that is added to the stain

• the amount of stain remaining

Multiple Choice

The type of ketchup and fabric should be the same for each stain. The vinegar and the detergent should be added to the stains for the same amount of time. These are examples of:

• constants

• hypotheses

• manipulated variables

Multiple Choice

The experiment should also include a third ketchup stain that shows what happens when neither vinegar nor detergent is added. This will be the:

• conclusion

• control

• variable