Delicate balance

Look! No hands!

Difficulty:
Danger:
Duration:
20 minutes

Safety

  • Carefully review the general safety advice on the back of the box cover before starting the experiment.
  • Read the "Magnets and electricity" section of the safety guidelines carefully before proceeding. Do not let children under 8 years old handle small magnets.
  • Disassemble the setup after the experiment.

Disposal

Dispose of solid waste together with household garbage.

Scientific description

You’ve seen that the magnets  repel each other when their like poles are facing one another. How will the magnets  behave if their like poles are above each other?

Two magnets  placed sideways or above each other feel both of their neighbor’s poles. If the magnets are close enough, they’ll turn  to let the attractive  force win, unless they are braced to restrict turning.

In this experiment, the magnets  are fixed and positioned one above the other so that like poles are closer than opposite poles. Therefore, they repel  each other, suspending the rod in midair without visible support. If you look at the installation from above, you can see that the rod is hovering  in the middle between the base magnets , since it is repulsed equally from both sides. If you gently nudge the rod to either side, the repulsion from that side increases and pushes the rod back to its original position (equilibrium).

Curiously, the rod can also rotate as long as the distance between the magnets on it and the base does not change.