the eeps Data Zoo
curator:Tim Erickson
Magnet Force 2

This is original data taken by a group of physics students at Mills High School in Millbrae, CA.

The setup is shown in the diagram at right. We're looking at the repulsive force between two magnets as a function of the distance between them. To get the force, one of the disk magnets is glued to a digital scale, and the other is gradually lowered from above. As the magnets get closer together, the repulsive force pushes down on the scale.

We have dist_cm, the distance in centimeters, and force_gf, the force in grams of force, that is, the number the scale reads.

Questions and tasks
How does the force depend on distance?
Explain that theoretically, if you can--or make a numerical model.
What effect does gravity have on this experiment? Does it matter that it's set up vertically? If there is a problem, what can we do to correct it?

dist_cm force_gf
18.0
0.01
17.0
0.02
16.0
0.02
15.0
0.04
14.5
0.05
14.0
0.06
13.5
0.07
13.0
0.08
12.5
0.09
12.0
0.09
11.5
0.10
11.0
0.13
10.5
0.16
10.0
0.20
9.5
0.24
9.0
0.29
8.5
0.39
8.0
0.48
7.5
0.60
7.0
0.77
6.5
1.01
6.0
1.27
5.5
1.82
5.0
2.58

<text form of the data>

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Last updated February 14, 2007
supported by NSF award DMI-0216656