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Static Electricity. 600 BCE Greek Thales = amber (elektron) and wool 16th century other substances behave the same way as amber. Electrically charged objects -electrified -either attract or repel each other -Franklin identified 2 types -positive and negative. Electrical Charges.
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Static Electricity 600 BCE Greek Thales = amber (elektron) and wool 16th century other substances behave the same way as amber
Electrically charged objects-electrified-either attract or repel each other-Franklin identified 2 types-positive and negative
Electrical Charges • positive protons (p+ tightly contained in the nucleus)carry a positive charge • electrons on the outer shell (valence e- ) can be transferred from 1 atom to another • negatively charged objects have more e- than p+
Electrical Charge • measured in Coulombs (C) • elementary charge = the charge carried by a single ____________ or ____________ • 1.602 x 10-19 C per electron or proton • 1 Coulomb = 1 C = the charge of 6.25 x 1018 electrons or protons • like charges repel/ opposite charges attract • Fatt or Frep • Law of Conservation of Charge
Conductors, Semiconductors and Insulators conductors permit the free flow of electrical charges = metals and carbon in the form of graphite insulators impede the free flow of electrical charges = nonmetals semiconductors are somewhere in between = metalloids
Static Electricity describes all the phenomena related to electrical charges at rest insulated charges which are immobile electroscopes
Charged Objects usually don’t remain permanently charged gradually lose charge to water molecules in the air (humidity) rapidly discharge when 2 oppositely charged objects come close together = electrostatic discharge
Charging an Object Friction Conduction Induction
Charging by Friction when 2 neutral insulators are rubbed together electrons move from 1 object to the other depends on the electrostatic series electrons move from the lower material to the higher material higher material becomes negative/lower material becomes positive
Charging by Conduction a charged object touches a neutral object the charges are shared evenly btw the 2 the 2 now have the same charge but weake than the original 1
Charging by Induction no direct contact btw the charged object and the neutral object opposite charges accumulate on the other side of the neutral object then touch other side of neutral object with a conductor charges transfer from the neutral to the conductor the “neutral” object becomes charged oppositely to the original charged object