Activity

Dancing magnets

Summary
A magnet on a string swings randomly and seemingly endlessly as it is attracted and repelled by other magnets. Can be used as a free experimentation activity.
Science content
Physics: Motion and Forces, Newton’s Laws, Gravity (K, 2, 6)
Physics: Energy forms, Conservation of Energy (1, 3, 4, 5)
Science competencies (+ questioning + manipulation + others that are in every activity)
Questioning/predicting: predicting (1 up), hypothesizing (7)
Planning/conducting: planning investigations (3 up)
Processing/analyzing: classifying data, finding patterns (1 up)
Processing/analyzing: comparing observations with predictions (1 up)
Processing/analyzing: considering alternative explanations (5 up)
Evaluating: inferring (3 up)
Magnet on a string hangs just above the magnets on a steel base
Use a steel saucepan as a base
Gently swing the magnet, then watch it slow down and dance
Arrange the magnets on the base to affect the hanging magnet
Lessons activity is in
Force stations
Magnet stations
Magnet stations and more magnets/electromagnets
Forces at-a-distance
Resource
Exploratorium snack: magnet pendulum
Materials
  • string to hang magnet
  • magnet with a hole in it (if none available, the string can be taped to the magnet)
  • tape, to tape the string to a table top (or use clamp stand or support for hanging the magnet)
  • 3 other identical round/flat magnets
  • flat steel base, to attach the 3 magnets to e.g. tin plate, oven tray or upturned saucepan (or use the base of the clamp stand)
Procedure

Adapted from the Exploratorium snack https://www.exploratorium.edu/snacks/strange-attractor

Lay the 3 identical magnets in a triangle under the support.
Hang the hole magnet so it is suspended between these 3 magnets, and is attracted to them, but does not touch them.
Gently swing the suspended magnet so that it moves irratically between the other 3 magnets.
Adjust the height and position of the suspended magnet, and the positions of the other 2 magnets until you get best results - the suspended magnet can swing for quite a while before it finds a stable position.

Try doing with a really long string from the ceiling.

Grades taught
Gr K
Gr 1
Gr 2
Gr 3
Gr 4
Gr 5
Gr 6