Static electricity is a very important concept in physics. In physics II, we conduct experiments with electroscopes, Van de Graaff generators, different cloth materials and some rods usually made of ebonite (hard rubber), glass, acrylic, and perhaps a few other things. You may be familiar with experiments that involve rubbing the cloths on the rods to generate a static charge. You may have asked yourself which cloths go with which rods?
Static electricity experiments are unreliable at times due to different conditions in the environment. For example, dust in the air and humidity can have a huge impact, making it hard to know if the cloths and rods are being used in the right combination.
There is a way to know which materials work best together to generate static charge through friction. The triboelectric series is a list of materials that indicates which materials are capable of acquiring a positive or negative charge and the relative strength of those charges. This is done with an ordered list as shown below in table 1. It acts like a solution manual for static electricity experiments.
|Typical Triboelectric Series|
|+ Positive Neutral – Negative||Air Skin (dry) Leather Rabbit Fur Glass Human Hair Mica Nylon Wool Cat Fur Lead Silk Aluminum Paper Cotton Steel Wood Lucite Amber Rubber Balloon Hard Rubber Nickel Copper Silver Gold, Platinum Polyester Polystyrene Acrylic Plastic Food Wrap Polyurethane Polypropylene PVC Teflon Silicone Rubber|
Using the chart above, for the objects rubbed together, identify the sign of the charge on the spoon, long rod, balloon, or pipe after it is rubbed with the other material:
|Copper pipe rubbed with fur|
|A rubber balloon rubbed on your hair|
|PVC pipe rubbed with a paper towel|
|Sterling silver spoon rubbed with a nylon cloth|
|Ebonite (hard rubber) long rod rubbed with a paper towel|
|Lead pipe rubbed with a paper towel|
|Aluminum rod rubbed with polyester cloth|
|Glass rod rubbed with wool cloth|
When rubbing certain materials against one another they can transfer negative charges, or electrons. Why is it that the electrons are the charges transferred in this process? Explain in the box below.
Go to the following: http://phet.colorado.edu/en/simulation/balloons-and-static-electricity
- How does static electricity work? Explain in the box below.
- Observe the balloon and sweater before anything happens. Is the overall charge on the sweater neutral, positive, or negative (circle one)?
- Observe the balloon and sweater before anything happens. Is the overall charge on the balloon neutral, positive, or negative (circle one)?
- Take the balloon in the simulation and rub it on the sweater. What is happening? Explain below.
- After you rub the balloon on the sweater in the simulation, is the overall charge on the sweater neutral, positive or negative (circle one)?
- After you rub the balloon on the sweater in the simulation, is the overall charge on the balloon neutral, positive or negative (circle one)?
- What happens when you move the balloon towards the wall after the steps above? Is there anything happening to the charges on the wall? Explain. See figure 1.
- Bring the balloon back towards the center of the screen as shown in figure 2 below. Keep it there with the mouse. Now let it go. What is the balloon attracted to (the wall or the sweater)? (Circle one)
- Why is the balloon attracted to either the wall or the sweater in question number 8? Explain.
- Take the balloon and put it on the wall. Let the balloon go. You should notice that the balloon sticks to the wall. Why is the balloon now sticking to the wall when it was attracted to the sweater before in number 8? Explain.
Go to the link and watch the following Youtube Video.
From watching the video explain why the person experiences a mild shock when touching the door. Explain in detail as they do in the video.
Youtube. (2018, April 4). Retrieved from https://www.youtube.com/watch?v=aokN-zJhus4