If an electron is stripped from a neutral atom, there is more protons than electrons, and the particle is said to be positive. Likewise, if an additional electron is added to a neutral atoms, it is said to be negative.
Not all atoms are the same. Some hold more tightly to their electrons than others. This is quantified by the triboelectric scale or series.
If a material readily gives up electrons, it is more positive on the triboelectric series. Also, if it is more apt to steal electrons, it is more negative. Here is a list of common house-hold materials and how they measure on the triboelectric series:. In order to tell how two substances will act when in contact with each other depends on their relative position on this scale. If two materials are several positions away from each other on the triboelectric series, there will be a charge separation.
The greater the position displacement, the greater the separation. When two non-conducting materials come in contact, a chemical bond forms, and depending on the triboelectric properties of the materials, a charge imbalance occurs due to one material capturing an electron from another material. Many scientists say that static is a deceptive term because static implies no motion, but in reality it is necessary for these imbalances to flow.
The sparks you feel and see come from the flow of this charge. Views Total views. Actions Shares. No notes for slide. Friction and the Electrostatic Series The simplest way to charge a neutral object is by friction.
Friction and the Electrostatic Series Charging by friction is the transfer of e- between 2 neutral objects that occurs when they are rubbed together or touch. Friction and the Electrostatic Series When rubbed together, different materials lose or gain e- more easily than others. Friction and the Electrostatic Series The Electrostatic Series ranks different materials on their ability to gain or lose electrons. They represent a collection of charges protons or electrons.
Total views 6, On Slideshare 0. From embeds 0. Number of embeds 4. Downloads 0. Shares 0. When you rub the glass rod with the silk, the rod charges positive.
If you place a charged rod on one of the swivel stands, and then bring another charged rod close to it, you can show electrostatic repulsion similarly charged rods or electrostatic attraction oppositely charged rods. This demonstration illustrates two things: triboelectricity and the electrostatic force. The electrostatic force is sometimes called Coulomb force or Coulombic force , after Charles Augustin Coulomb. He was the first person to attempt to measure it directly, though other, indirect, measurements preceded his.
The Coulomb , the unit of electrostatic charge, is named after him. See demonstration Since this demonstration does not allow for direct measurement of the electrostatic force between the two rods, it is merely qualitative in nature.
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