How can we know that which thing or body has positive or negative charge? How can we identify the nature of charge?
When you rub two different materials together, the friction between them produces a positive charge in one and a negative charge in the other. To determine whether one of them has a positive or negative charge, you can refer to a triboelectric series, which is a list of known materials sorted by increasing negative charge. Rubber, for example, is lower on the list than wool, so stroking rubber with wool will reliably create a negative charge in the rubber. Knowing this, and armed with an electroscope for measuring charge, you can determine whether the charge of an object is positive or negative.
Triboelectric Series Common materials are listed according how well they create static electricity when rubbed with another material, as well as what charge the material will possess.
Become positive in charge The following materials tend to give up electrons when brought in contact with other materials. That means they will have an increase of positive (+) charges.
The materials are listed with those that have the greatest tendency to give up electrons at the top to those that barely give up electrons.
Materials that gain a positive (+) electrical charges
(Tend to give up electrons) Most (+) charges Air Greatest tendency for giving up electrons and becoming highly positive (+) in charge Dry human skin Greatest tendency of a solid to give up electrons and becoming highly positive (+) in charge Leather
Rabbit fur
Fur is often used to create static electricity Glass
The glass on your TV screen gets charged and collects dust Moderate (+) charges Human hair
"Flyaway hair" is a good example of having a moderate positive (+) charge Nylon
Wool
Lead
A surprise that lead would collect as much static electricity as cat fur Cat fur
Silk
Aluminum
Gives up some electrons Least (+) charges Paper
Neutral There are very few materials that do not tend to readily attract or give up electrons when brought in contact or rubbed with other materials.
Materials that are relatively neutral Cotton
Best for non-static clothes Steel
Not useful for static electricity
Become negative in charge The following materials tend to attract electrons when brought in contact with other materials. They are listed from those with the least tendency to attract electrons to those that readily attract electrons.
Materials that gain a negative (−) electrical charges
(Tend to attract electrons) Least (−) charges Wood
Attracts some electrons, but is almost neutral Amber
Hard rubber
Some combs are made of hard rubber Nickel, Copper
Copper brushes used in Wimshurst electrostatic generator Brass, Silver
Gold, Platinum
It is surprising that these metals attract electrons almost as much as polyester Polyester
Clothes have static cling Styrene (Styrofoam)
Packing material seems to stick to everything Moderate (−) charges Saran Wrap
You can see how Saran Wrap will stick to things on (+) list Polyurethane
Polyethylene (like Scotch Tape)
Pull Scotch Tape off (+) surface and it will become charged Polypropylene
Vinyl (PVC)
Many electrons will collect on PVC surface Silicon
Most (−) charges Teflon
Greatest tendency of gathering electrons on its surface and becoming highly negative (−) in charge
Triboelectric Series
Common materials are listed according how well they create static electricity when rubbed with another material, as well as what charge the material will possess.
Become positive in chargeThe following materials tend to give up electrons when brought in contact with other materials. That means they will have an increase of positive (+) charges.
The materials are listed with those that have the greatest tendency to give up electrons at the top to those that barely give up electrons.
| Materials that gain a positive (+) electrical charges (Tend to give up electrons) | ||
| Most (+) charges | Air | Greatest tendency for giving up electrons and becoming highly positive (+) in charge |
| Dry human skin | Greatest tendency of a solid to give up electrons and becoming highly positive (+) in charge | |
| Leather | ||
| Rabbit fur | Fur is often used to create static electricity | |
| Glass | The glass on your TV screen gets charged and collects dust | |
| Moderate (+) charges | Human hair | "Flyaway hair" is a good example of having a moderate positive (+) charge |
| Nylon | ||
| Wool | ||
| Lead | A surprise that lead would collect as much static electricity as cat fur | |
| Cat fur | ||
| Silk | ||
| Aluminum | Gives up some electrons | |
| Least (+) charges | Paper |
There are very few materials that do not tend to readily attract or give up electrons when brought in contact or rubbed with other materials.
| Materials that are relatively neutral | ||
| Cotton | Best for non-static clothes | |
| Steel | Not useful for static electricity |
The following materials tend to attract electrons when brought in contact with other materials. They are listed from those with the least tendency to attract electrons to those that readily attract electrons.
| Materials that gain a negative (−) electrical charges (Tend to attract electrons) | ||
| Least (−) charges | Wood | Attracts some electrons, but is almost neutral |
| Amber | ||
| Hard rubber | Some combs are made of hard rubber | |
| Nickel, Copper | Copper brushes used in Wimshurst electrostatic generator | |
| Brass, Silver | ||
| Gold, Platinum | It is surprising that these metals attract electrons almost as much as polyester | |
| Polyester | Clothes have static cling | |
| Styrene (Styrofoam) | Packing material seems to stick to everything | |
| Moderate (−) charges | Saran Wrap | You can see how Saran Wrap will stick to things on (+) list |
| Polyurethane | ||
| Polyethylene (like Scotch Tape) | Pull Scotch Tape off (+) surface and it will become charged | |
| Polypropylene | ||
| Vinyl (PVC) | Many electrons will collect on PVC surface | |
| Silicon | ||
| Most (−) charges | Teflon | Greatest tendency of gathering electrons on its surface and becoming highly negative (−) in charge |
