The other day we did an experiment with a grade ten class with static electricity with a machine called a Van der Graff. An object surrounded by a metal ball with a chain inside that moves according to how high you turn the dial. To try out this experiment our teacher chose volunteers to stand on a few layers of Styrofoam in front of the Van der Graff and either put one or both of your hands on top of it.
The first experiment we did with the Van der Graff was nice and simple, the grade tens were reviewing the object while the grade nines were spectating what it did for the first time. Our science teacher chose a student to stand on top of the Styrofoam in front of the Van der Graff and just put both his hands on top of the machine to charge up. They have to stand on top of the Styrofoam because it blocks the completion of the electric charge, if they were standing without the Styrofoam the electrons would enter their body and exit to the ground, you would still get a charge but not as much. The Styrofoam works as an insulator, blocking all electricity, so when the electrons enter your body they have nowhere to go and instead store up, creating a bigger shock.
It was really funny every time a new person went onto the machine because as their body got charged up their hair raised and most of the time looked ridiculous. They wanted me to try out the Van der Graff because my hair is purple and they claimed my hair was “just the right length to poof” but I didn’t want to, so someone else went instead. After the volunteer was charged up front the Van der Graff he removed his hands from the machine and our teacher used the discharge stick, a stick with a cylinder of metal at the end, to touch the top of the metal ball to take the electric charge away from the machine so she wouldn’t get a charge. She then got someone to come up and touch the volunteer who was charged from the Van der Graff. When the person touched the volunteer they both jumped from the static electricity jumping from one body to the other, equaling out the protons and electrons, we even all heard the shock.
The next experiment a volunteer stood with the Styrofoam in front of the Van der Graff with paper shreds in one hand and touching the machine in the other, I wasn’t quite sure what was going to happen and I’m not too familiar with the properties of static electricity yet so I predicted that the paper would all stick together. My prediction was wrong, instead of sticking together, the paper shreds instead separated and flew away from each other and from the volunteer’s hand, landing on the table below. The volunteer then was told to hold their hand just above the table where the shreds were and to touch the machine. This time I thought the paper would fly up to her hand and stay there. I was half right, but instead of flying up and staying there, the shreds would fly up and flutter around her hand before falling back down, but the shreds were always in motion no matter what.
Our science teacher then placed several paper muffle tins on top of the Van der Graff and then she put several metal muffin tins on top of the Van der Graff. I believe they were both suppose to do different things but they both ended up doing the same thing, flying off of the Van der Graff and (semi) separating as they flew away.
As one of our last experiments our grade nine and grade ten science classes took turns making a human chain, there was someone touching the van der Graff and someone who was touching the sink faucet, and everyone in between the two held hands. The person holding the Van der Graff first put their hand on the machine, turned it on, and let their body build up a charge, and then when they had enough of an electric charge they grabbed the hand of the next person, and since person number two and onward were already holding hands the chain shock begun and exited through the sink faucet at the end. I was not part of this final experiment but it seemed like everyone felt this shock, some people only a little bit, and some people a lot but I’m not sure why. I am curious to know what would have happened if there wasn’t someone touching the sink.
My favorite part of this activity was probably seeing everyone react to the Van der Graff and the physical changes that I could see happy to them, like their hair flying up or seeing them react to the shock. Even if I don’t quite understand it fully yet, this activity definitely gave me a better understand on static electricity and it’s important to remember because in the future and I can reflect on this activity and remember what happens with static electricity.