physics2 - Electricity This item is copyrighted, and was...

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Electricity This item is copyrighted, and was created by those from “theeseller555.” The only authorized seller of this item is theeseller555. Electric Forces: Section 1. Net Electrical Charge Matters are made of atoms. An atom is basically composed of three different components -- electrons, protons, and neutrons. An electron can be removed easily from an atom. Normally, an atom is electrically neutral, which means that there are equal numbers of protons and electrons. Positive charge of protons is balanced by negative charge of electrons. It has no net electrical charge. When atoms gain or lose electrons, they are called " ions ." A positive ion is a cation that misses electron(s). A negative ion is an anion that gains extra electron(s). What is charge? Objects that exert electric forces are said to have charge. Charge is the source of electrical force. There are two kinds of electrical charges, positive and negative. Same charges (+ and +, or - and -) repel and opposite charges (+ and -) attract each other. Section 2. Conductors and Insulators Substances can be classified into three types -- insulators, conductors, and semiconductors. Insulators are materials which allow very little electrical charges and heat energy to
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flow. Plastics, glass, dry air and wood are examples of insulators. Conductors are materials which electrical charges and heat energy can be transmitted very easily. Almost all metals such as gold, silver, copper, iron, and lead are good conductors. Semiconductors are materials which allow the electrical charges to flow better than insulators, but less than conductors. Examples are silicon and germanium. Example Problem 1. Which one of these is a conductor? (a) dry air (b) lead (c) silicon (d) glass (e.g. "a" ) Section 3. Charged Objects When two objects are rubbed together, some electrons from one object move to another object. For example, when a plastic bar is rubbed with fur, electrons will move from the fur to the plastic stick. Therefore, plastic bar will be negatively charged and the fur will be positively charged. a. Methods of Charging (Electroscope) When you bring a negatively charged object close to another object, electrons in the second object will be repelled from the first object. Therefore, that end will have a negative charge. This process is called charging by induction .
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When a negatively charged object touches a neutral body, electrons will spread on both objects and make both objects negatively charged. This process is called charging by conduction . The other case, positively charged object touching the neutral body, is just the same in principle. (Electroscope) Section 4. Unit of Electrical Charge: The Coulomb " C " The symbol for electric charge is written q, -q or Q. The unit of electric charge is coulomb "C". The charge of one electron is equal to the charge of one proton, which is 1.6 * 10 -19 C. This number is given a symbol "e". Example Problem 2.
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physics2 - Electricity This item is copyrighted, and was...

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