Science Buddies: "Ask an Expert"

Hello,
I was wondering if anyone new how you would make groups when measuring the amount of static electricity created When creating various amounts of friction.
Thanks.

How do you make groups of anthing? This comes down to figuring out how to classify the things you are trying to group.

We need to know more about what you are trying to prove or disprove. Have you read up on the Scientific Method and your question under getting started https://www.sciencebuddies.org/science- ... ndex.shtml?

If you haven't, then I recommend you start there to formulate a hypothesis. Once you have the hypothesis (what you are trying to prove or disprove), then it might be obvious how you want to group things. If not, state your hypothesis here and we can better help you once we know what you are trying to accomplish.

Okay, this is my hypothesis
"If I create a lot of friction, than it will create more static electricity than if I create less friction."
I'm not sure how to set up trial groups for this hypothesis.
Do you know how to?
Thanks

Jimmy Walker wrote:"If I create a lot of friction, than it will create more static electricity than if I create less friction."

I'm probably going to use some terms that are new to you and you will have to look them up and attempt to understand them...

Frictional forces result from a "normal force" pushing materials together and result in a "drag force" that resists the sliding of two materials against each other. In order to generate static electricity, the materials you use have to be a pair electrical insulating materials that will transfer electrons when rubbed together (one is an electron donor e.g. cathode and the other is an electron receptor e.g. annode).

Since your choice of materials will determine the coefficient of friction, the only way to increase friction for a given pair of objects is to increase the normal force or increase the surface area. That means it will take more force to move the objects.

If you have a different
1) amount of surface area, or
2) different materials between two trials, or
3) number of strokes, or
4) speed of the strokes, or
5) length of the strokes, or ...
you will have other variables besides friction that will differ between your trials and you won't be able to draw any conclusions.

You also have the problem of how to transfer the static charge you build up in order to measure it and have to deal with dielectric leakage paths. If one of the objects is compressible (gets thinner when normal for is increased), its dielectric properties are likely affected as well. Any change in dielectric leakage could significantly affect your results.

This is going to be a challenging hypothesis to test in a scientifically valid way.