5B10.25 – Van der graaff [flying hats]

This demonstration is an entertaining visualization of the induction of charges and its repelling effect due to opposite values.

1. The first variation of the experiment is with the van der graaf generator as the power source. Properly ground the generator and attach the cup holder accessory to the top of the sphere. Put a few aluminum hats inside the holder [for a bigger effect, the more cups placed the better]. Turn on the van der graaf [starting from the lowest power], as you increase the charge more cups will start to fly out and scatter outside of the holder. At the end discharge the sphere and collect the cups.
2. The second version of the experiment is with the Wimshurst machine as the charge source. It can hold fewer cups at once, but it charges the cups slower and illustrates the effect with manual induction. The cups should be placed on one of the small charging spheres. Then the plates should be rotated in the direction given on the equipment [an arrow]. As the charge builds up, the cups will slowly fly away. At the end the two charged spheres should be discharged by touching each other.