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Day 1 Electric Charge

Static Electricity; Electric Charge and Its Conservation Electric Charge in the Atom Insulators and Conductors Objectives

The Elementary Electric Charge is called e Like charges repel, unlike charges attract Charges come in two types: (+e) & (- e) where e = x Coulombs `

Objects can be charged by rubbing (ie: rubber rod becomes negative when rubbed with rabbit pelt, glass rod becomes positive when rubbed with silk )

Charge Carriers The primary charge carrier is the electron An object has a net negative charge if it is given excess electrons An object has a net positive charge if it has an electron debt.

Objects are considered to be electrically neutral if the object has the same number of (+) charges as (-) charges A neutral atom has the same number of electrons as protons A neutral atom is said to be ionized if one or more of its valence electrons is added or removed Electric charge cannot be created or destroyed. This is called Conservation of electric charge

Some molecules are said to be Polarized if the charges of the constituent atoms are not uniformly distributed. A Polar Molecule is overall electrically neutral

Insulators & Conductors Materials that inhibit the flow of electric charge over its surface are called an electrical insulator ie: wood, plastic (PVC), glass, rubber Materials that permit the flow of electric charge over its surface are called electrical conductors ie: Metals such as Gold, Silver, Copper, Aluminum Materials which can exhibit intermediate amounts of electrical conductivity are called semi-conductors ie: Silicon, Germanium, Gallium Arsenide

Conductor: Charge flows freely Metals Insulator: Almost no charge flows Most other materials