Magnetic Exploration Part 4: Field Visualizer

Author(s): Seth Bush
Subject: Physics
Grade Level(s): Grade 4
Topic: Magnetism
Big Idea(s):

Students know that magnets have two poles (north and south) and that like poles repel each other while unlike poles attract each other.
Students know how to build a simple compass and use it to detect magnetic effects, including Earth’s magnetic field.
Differentiate observation from inference (interpretation) and know scientists’ explanations come partly from what they observe and partly from how they interpret their observations.
Formulate and justify predictions based on cause-and-effect relationships.
Conduct multiple trials to test a prediction and draw conclusions about the relationships between predictions and results.
Follow a set of written instructions for a scientific investigation.

What you need:

Field Graphing paper
Magnet Kit
Compass
Pencil
Scotch Tape
Sealed Iron Fillings Case

Summary:

Field Visualizer; is a multipart activity in which you will use compasses and iron
filings

Learning Goals / Objectives:

1.) Students will gain a hands on understanding of many properties of permanent magnets. In particular they will learn

About magnetic poles and their interactions with each other
How to visualize and measure magnetic fields
What materials are magnetic and what materials are not magnetic
How to characterize the field strength of a permanent magnet

Anticipatory Set:

Driving Questions
1.) How do magnets work?
2.) How does a compass work?
3.) How can we “see” magnetic fields?

Instructions / Activities:

In this series of activities we are going to attempt to visualize magnetic fields using:

A compass and field graphing paper
Iron filing in a sealed clear plastic box

Pen and Paper;
Work independently.

In this activity we use a compass to map the magnetic field of your favorite magnet.

Make sure you have the following:

your favorite magnet
field graphing paper
a compass (the small ones will work best)
a pencil
scotch tape

1.) If you haven’t already done so, label the North and South poles of your favorite magnet.

2.) Put your favorite magnet at the center of the field graphing paper with the North pole of the magnet pointing towards the top of the paper. Use a small piece of tape to fix the magnet in place.

3.) Systematically test the magnetic field at each point on the field graphing paper. Put your small compass at each and record the direction of the compass arrow directly on the field graphing paper.

4.) On a second piece of field graphing paper, arrange and fix your magnet such that the south pole faces the top of the paper.

5.) Repeat the field mapping (part 3).

6.) Any surprises? Share your results with your neighbor. Post your results at the front of the room on the whiteboard.

Iron Filings;
Work in groups of 2.

In this activity we use a sealed case of iron filings to observe magnetic filed lines.

Make sure you have the following:

your favorite magnet
the sealed iron filings case

1.) Bring the North pole of,your favorite magnet close to the filings box. What happens to the filings?

2.) Look closely at how the filings orient themselves. Draw a sketch of your observations in your note book.

3.) Predict what will happen when you bring the South pole close.

4.) Bring the South pole of your favorite magnet close to the filings box.

5.) Look closely at how the filings orient themselves. Draw a sketch of your observations in your notebook. Did it behave as you predicted?

6.) Predict how the filing might orient them selves if the magnet was brought in on its side.

7.) Turn the magnet on its side and bring it close to the filings box.

8.) Look closely at how the filings orient themselves. Draw a sketch of your observations in your notebook. Did it behave as you predicted?

9.) Any surprises? Share your results with your neighbor.

Assessment:

Teacher’s Discretion

Wrap-up / Closure: