Download Lab 2: Magnetic Fields - Island Energy Inquiry

LAB 2: MAGNETIC FIELDS
Lab 2: Magnetic Fields
Materials Needed:
Transparent graph
Iron filings box
3 different magnets
Colored pencils
Compass
Highlighter/whiteboard markers
Safety:
Take care when handing the iron filings boxes. If filings escape, students should wash hands
immediately and avoid eyes.
Engaging Activity
Tell the class you are giving each student a magical rock. After distributing magnets to all students,
ask students to convince you that what they are holding is more than a rock (a magnet). Ask
students to work in pairs to come up with at least two concrete reasons. Have students share
their examples that prove magnetic properties.
Next ask students if all their magnets are “created equal”. Do they all repel and attract the same?
Do they all have the same kinds of properties? Explain that the next lab will allow students to
observe the magnetic field and understand similarities and differences between their magnets.
Students groups each need an iron filing box, 3 different
magnets, 3 transparency grids, compass, colored pencil, and
the lab sheet Lab 2: Magnetic Fields.
Ask students to tape the transparency to the filing box. After
spreading the filings by shaking, students place a magnet under
the box. Discuss observations. How do the filings help you
detect the magnetic field? Instruct students to slowly move
a compass around the magnet. Ask, how does the compass
help you detect the magnetic field? Can a compass be a tool
to replace the filings? Can you visually detect differences in
magnetic field strength? How far does magnetic field reach?
Does it have a specific area (begin to be quantitative)?
After students have observed differences in iron filing
behaviors between strong and weak magnetic fields, use
highlighters or whiteboard markers to color in the magnetic
field on the transparency. From the grids, students can
determine strong magnetic field area by counting square units.
MAGNETISM, ELECTRICITY AND MOVEMENT
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LAB 2: MAGNETIC FIELD
Lab 2: Magnetic Field
Name: ______________________________________Date: ____________________________
Question:
What magnet has the (circle) strongest weakest magnetic field?
Hypothesis:
If the __________________magnet is used then the observed magnetic field is
(circle) larger smaller the than other magnets.
Data:
Observe what happens to the filings in the box when you move the magnet. Decide as a team what kind of filing behavior will
be considered a strong and weak magnetic field.
Strong square cm magnetic field looks like:
Weak square cm magnetic field looks like:
Magnet Shape
Qualitative Data:
Color in the squares where you see the strong magnetic field.
Area Grid Showing Magnetic Field Strength
A
B
C
D
E
F
G
H
I
J
K
L
1
2
3
4
STRONG
5
6
7
WEAK
8
Quantitative Data:
Count the squares you
colored and write the
unit area.
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LAB 2: MAGNETIC FIELDS
Lab 2: Magnetic Field
Magnet Shape
Magnet Shape
Qualitative Data:
Qualitative Data:
Color in the squares where you see the strong magnetic field.
Color in the squares where you see the strong magnetic field.
Area Grid Showing Magnetic Field Strength
A
B
C
D
E
F
G
H
I
J
K
Area Grid Showing Magnetic Field Strength
L
A
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
Quantitative Data:
B
C
D
E
F
G
H
I
J
K
L
STRONG
WEAK
Quantitative Data:
Count the squares you
colored and write the
unit area.
Count the squares you
colored and write the
unit area.
Results:
Using <, > , or = symbols describe the magnetic field strengths of the three magnets you tested.
_________________________________________________________________________________________
Conclusion:
The _______________ magnet has the strongest magnetic field. I can tell because ___________________________
__________________________________________________________________________________________
Did your results agree with your hypothesis? (Circle)
Explain why you decided to circle yes or no.
Yes, supported!
No, not supported!
__________________________________________________________________________________________
__________________________________________________________________________________________
MAGNETISM, ELECTRICITY AND MOVEMENT
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LAB 2: MAGNETIC FIELD
Lab 2: Magnetic Field
Extensions
In order to develop skills towards choosing appropriate measurement tools, students may repeat
the lab using area grids of different sizes. Does the size of squares (measurement) change the
area? Are smaller or larger squares more accurate? Students might also analyze results using bar
graphs to compare Strong Magnetic Field Area vs. Magnet Type. Accelerated students may also
create pie charts to show percentages of Strong, Medium, and Weak Magnetic Fields, but be sure
to have a discussion of what these percentages mean. Magnetic fields continue indefinitely, but
grow weaker from the source; a small area on the grid, has a small percent. This describes a ratio
to the space tested – not infinite space! This discussion would highlight the limitation of graphs
to represent data!
Create pie or bar charts together with your class using NCES:
http://nces.ed.gov/nceskids/createagraph/
Students may also diagram magnetic interactions, such as noticing the magnetic field lines
attraction or repulsion using the iron filings with pairs of magnets.
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