# A Shocking Discovery

## The Problem

What material makes the best static electricity?

## The Hypothesis

I think that cotton will create the most static electricity because whenever I wear cotton clothes I get shocked with static electricity.

## The Variables

Independent Variables:

• The material that will be rubbed against the balloon

Dependent Variable:

• Which material creates the most static electricity

Controlled Variables:

• Same balloon
• Same force of rubbing
• Same place on the balloon
• Same electroscope

## Procedure

1. Gather the materials listed
2. Have the electroscope ready nearby the testing area
3. Rub the test material against the balloon
4. Quickly move the balloon nearby the electroscope
5. Observe the reaction of the aluminum foil leafs inside the jar
6. Rate the reaction from 1 to 5
7. Repeat steps 3-6 for each material
8. If the balloon builds up static between charges, applying some water to the balloon then drying will relieve the build up.

## Key Words

• Static Electricity
• Triboelectric

## Research Notes

• Static Electricity is the imbalance of electrons between two objects
• It is created by the two objects making and then breaking contact with each other
• At least one of the objects has to be an insulator, and the other can be a conductor, but it works better if both materials are insulators
• Different materials have different abilities to attract and give electrons
• Polyurethane foam has a very strong affinity for surrendering electrons, while teflon can easily accept them
• There are other factors that affect static electricity that are not in my experiment like humidity and temperature: This is why cold, dry days are good for creating static electricity

## Results

1. Hair = 5
2. Leather = 4.5
3. Cotton = 4
4. Silk = 3.5
5. Aluminum = 3
6. Paper = 2
7. Plastic Wrap = 2
8. Scotch Tape = 2
9. Penny = 1.5
10. Polyester = 1

## Conclusion

My hypothesis was wrong. I was close, though. Cotton was the third best at creating static electricity, with a rating of 4. The highest was hair, with a score of 5. In my research, I found that cotton was actually a neutral on the triboelectric scale instead of a positive, and neutrals don't give up as much electrons as positives like hair do.

But I knew which materials were going to have the least static electricity, because the ones with the least electricity were negative on the triboelectric scale and so was the balloon, so neither was going giving up many electrons to each other.