Static electricity is a type of charge that is in a stationary state. In dry and windy autumn, people often encounter this phenomenon in their daily lives: when undressing and sleeping at night, crackling sounds are often heard in the dark, accompanied by blue light; When shaking hands when meeting, as soon as your fingers touch the other person, you will suddenly feel a piercing pain like a needle in your fingertips, which is shocking and disconcerting; When I wake up in the morning to comb my hair, it often "floats" and becomes more and more messy; When you pull the door handle or turn on the faucet, you will "get an electric shock" and often make a "popping" sound, which is the static electricity that occurs in the human body. The so-called static electricity is a static or non flowing charge (the flowing charge forms an electric current). When charges accumulate on an object or surface, static electricity is formed, and charges are divided into positive and negative charges, which means that electrostatic phenomena are also divided into two types: positive and negative static electricity. When positive charges gather on an object, positive static electricity is formed. When negative charges gather on an object, negative static electricity is formed. However, whether it is positive or negative static electricity, charge transfer occurs when a static object contacts a zero potential object (grounded object) or an object with a potential difference, which is the phenomenon of spark discharge that we see in daily life. For example, in northern winter, the weather is dry, and the human body is prone to static electricity. When it comes into contact with others or metal conductors, discharge phenomena will occur. People may experience a tingling sensation of electric shock, and sparks can be seen at night, which is the reason why chemical fiber clothing rubs against the human body and carries positive static electricity. (With basic physical knowledge, we know that rubber rods rub against fur, with rubber rods carrying negative charges and fur carrying positive charges). Static electricity is not static electricity, it is electricity that temporarily stays at a certain location on a macro level. When a person stands up on a carpet or sofa, the voltage of the human body can also be more than 10000 volts, and the static electricity on the surface of rubber and plastic films can be as high as 100000 volts. Matter is composed of molecules, molecules are composed of atoms, and atoms are composed of negatively charged electrons and positively charged protons. Under normal conditions, an atom has the same number of protons and electrons, and is in a positive and negative equilibrium, thus exhibiting an uncharged state to the outside world. However, electrons surround the atomic nucleus, and upon external force, they detach from the orbit, leaving the original atom A and invading other atoms B. The A atom carries a positive charge due to the reduction of the number of electrons, which is called a cation; The B atom exhibits a negative charge due to an increase in the number of electrons, known as an anion. The reason for the uneven distribution of electrons is that electrons are separated from their orbits by external forces, which contain various energies (such as kinetic energy, potential energy, thermal energy, chemical energy, etc.). In daily life, any two objects of different materials that come into contact and then separate can generate static electricity. When two different objects come into contact with each other, it causes one object to lose some charge, such as transferring electrons to another object to make it positively charged, while the other object gains some remaining electrons and becomes negatively charged. If the charge is difficult to neutralize during the separation process, it will accumulate and cause the object to carry static electricity. So when an object comes into contact with other objects and separates, it will carry static electricity. Usually, when peeling a plastic film from an object, it is a typical "contact separation" electrification, and the static electricity generated by taking off clothes in daily life is also "contact separation" electrification. Solids, liquids, and even gases can carry static electricity due to contact separation. This is because gases are also composed of molecules and atoms, and when air flows, molecules and atoms will also undergo "contact separation" and become electrified. We all know about friction electrification and rarely hear of contact electrification. Essentially, frictional electrification is a process of contact and separation that causes an imbalance between positive and negative charges. Friction is a process of continuous contact and separation. Therefore, frictional electrification is essentially contact separation electrification. In daily life, various objects may generate static electricity due to movement or friction. Another common type of electrification is induction electrification. When a charged object approaches an uncharged object, negative and positive charges are induced at both ends of the uncharged conductor