Static electricity related knowledge

Matter is made up of molecules, molecules are made up of atoms, and atoms are made up of negatively charged electrons and positively charged protons. Under normal circumstances, the number of protons and electrons in an atom is the same, and the positive and negative balance, so it is uncharged. However, electrons surround the nucleus, and once they are forced out of orbit, they will leave the original atom and invade other atoms B. Atom A is positively charged due to the lack of electron number, which is called cation, and atom B is negatively charged due to the increase of electron number, which is called anion. The reason for the uneven distribution of electrons is that electrons are out of orbit due to external forces, which include various energies (such as kinetic energy, potential energy, thermal energy, chemical energy, etc.). ). In daily life, any two objects with different materials will generate static electricity after contact and separation.

When two different objects touch each other, one object will lose some charges, for example, electrons will be transferred to the other object to make it positively charged, while the other object will gain some remaining electrons and be negatively charged. If it is difficult to neutralize the charge in the separation process, the charge will accumulate and make the object electrostatic. Therefore, when an object contacts and separates from other objects, it will be charged with static electricity. Usually, peeling plastic film from an object is a typical "contact" electrification, and the static electricity generated by undressing in daily life is also a "contact" electrification.

Solids, liquids and even gases are charged with static electricity due to contact. This is because gas is also composed of molecules and atoms, and when air flows, molecules and atoms will also produce "contact separation" and generate electricity.

We all know friction electrification, but we seldom hear of contact electrification. Essentially, triboelectrification is a process of contact and separation, which results in the imbalance of positive and negative charges. Friction is a process of continuous contact and separation. Therefore, triboelectrification is essentially contact electrification. In daily life, all kinds of objects may generate static electricity due to movement or friction.