The Van De Graff - Observations

A Van De Graff takes electrons from a bottom brush and moves them up to another brush. Then expels them into a metal dome attached to the top.

We conducted multiple tests such as blowing bubbles near the Van De Graff, forming a human chain, putting napkins on top and then just putting one and a couple more tests.

• When we blew bubbles near the Van De Graff they were at first attracted to the dome but then once it got closer they flew away and were repelled by the metal dome.
• Forming the human chain and having two people place their hand on the dome, enclosing the chain made all the participants gain electrons and making them positive or negative. While all the others who did not join the chain stayed neutral and when we touched them, the two touching got shocked.
• Multiple napkins flew away once we turned on the Van De Graff. But with one napkin, it stayed and started to get sucked in. I think the reason why one napkin stayed and got sucked in was mostly because of the lightness of it and the electrons pulling the bottom napkin in.
• Taping the stripes on the dome and turning on the Van De Graff made the stripes float up showing that the paper stripes were being repelled by the domes electrons. But, when you place the ground wand near the metal dome the small stripes are again attracted to the dome.
• Placing the cheerios on top of the dome and turning it on made the cheerios fly off within seconds. I think they flew off because of the imbalance of electrons.