oneone EEM-6A Objective: To conduct static electricity experiments in order to determine how charged objects affect each other. Energy Note: How do charged objects affect one another? Drill: 1. Take out yesterday’s paper. 2. Get a new ditto form the SET. 3. In your drill book write the ways that charged and neutral particles affect each other.

oneone EEM-6A Interactions Between Charged Particles The two types of charged particles interact in specific ways. 1.Charged particles that are the same repel each other. 2.Charged particles that are opposite attract each other. 3.Neutral particles have no effect on charged particles or other neutral particles.

oneone EEM-6A DITTO 1-1 Electric Charges 1.Start in Class 2.Complete for Homework

oneone EEM-6A STATIC ELECTRICITY AND THE ATOM Atoms have three subatomic particles, the neutron, the proton, and the electron. The charged particles of an atom are the protons and the electrons. The protons are in the nucleus of the atom and have a positive ( + ) charge. The electrons occupy the space surrounding the nucleus and have a negative ( - ) charge. These two particles interact in a specific way. Particles with the same charge repel each other. Particles with different charges attract each other.

oneone EEM-6A STATIC ELECTRICITY AND THE ATOM If matter consists of charged particles, why aren’t you attracted to or repelled by all of the objects around you? The reason is that each atom has an equal number of protons and electrons. Each positive charge is balanced by a negative charge. The charges cancel out and the object as a whole is neutral. However, there are times when atoms can gain or lose an electrical charge. Remember, protons are bound tightly in the center of atom. Electrons, however, can sometimes leave their atoms.

oneone EEM-6A STATIC ELECTRICITY AND THE ATOM Whether or not an electron will move depends on the material. Atoms in insulators, such as rubber, plastic and glass, hold their electrons tightly. Atoms in conductors, such as gold, silver, copper, and aluminum, hold some of their electrons loosely. These electrons move freely from atom to atom within the material.

oneone EEM-6A STATIC ELECTRICITY AND THE ATOM Neutral objects can become charged if the atoms in the objects gain or lose electrons. If an object loses electrons, it is left with more protons. Therefore, the object will have an overall positive charge. If an object gains electrons, it has more electrons than protons. Thus it will have an overall negative charge.

oneone EEM-6A STATIC ELECTRICITY AND THE ATOM The area affected by the overall charge of an object is that object’s electric field. Remember that charges are not created or destroyed. If an object gives up electrons, another object gains those electrons. This is known as the conservation of charge. See Figure 1, “Charging Matter” on your ditto, to help clarify this concept.

oneone EEM-6A STATIC ELECTRICITY AND THE ATOM There are three methods by which charges are transferred, friction, conduction, and induction. 1.Friction is the transfer of electrons from one object to another by rubbing. 2.Conduction is the transfer of electrons from a charged object to another by direct contact. 3.Induction is the movement of electrons to one part of an object by the electric field of another object.

oneone EEM-6A STATIC ELECTRICITY AND THE ATOM An object that gains a static charge doesn’t hold the charge forever. Electrons tend to move, returning the object to its neutral condition. When a negatively charged object and a positively charged object are brought together, electrons move until both objects are neutral. The loss of static electricity as electric charges move off an object is called static discharge.

oneone EEM-6A HOMEWORK 1. Complete Charges Ditto