McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved Electricity Principles & Applications Eighth Edition Chapter 1 Basic Concepts (student version) Richard J. Fowler McGraw-Hill 1 - 1

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved INTRODUCTION Work and Energy Atoms Ions Charge

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved Dear Student: This presentation is arranged in segments. Each segment is preceded by a Concept Preview slide and is followed by a Concept Review slide. When you reach a Concept Review slide, you can return to the beginning of that segment by clicking on the Repeat Segment button. This will allow you to view that segment again, if you want to.

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved Work and Energy

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved Concept Preview Energy and work are interrelated terms. Energy can be converted from one form of energy to another form of energy. W is the symbol for both work and energy. The Joule (J) is the unit for both

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved Work (W) consists of a force moving through a distance. Energy (W) is the capacity to do work. The joule (J) is the base unit for both energy and work. The amount of work done equals the amount of energy used (converted). Fifty joules of energy are required to do fifty joules of work.

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved A cell converts chemical energy to electric energy. A light bulb converts electric energy to light energy and heat energy. ENERGY CONVERSION

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved ENERGY QUIZ The _____ is the base unit of energy. joule The symbol for the base unit of work is the letter _____. J The italicized upper-case _____ is the symbol for energy. W Doing forty joules of work requires _____ joules of energy. forty A light bulb converts _____ energy into _____ energy and _____ energy. electric light, heat

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved Concept Review Repeat Segment energy and work are closely related energy can be converted from one form of energy to another form of energy W is the symbol for both work and energy the Joule (J) is the unit for both

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved PARTICLES OF THE HELIUM ATOM

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved Concept Preview Electrons are always in motion. Electrons and protons have an electric charge. Atoms contain electrons, protons, and neutrons.

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved Protons (+ charge)

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved Protons (+ charge) Neutrons (no charge)

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved Protons (+ charge) Neutrons (no charge) Electrons (- charge)

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved The electrons’ orbital paths are shown by the dashed lines. The electrons orbit around the nucleus (neutron/proton cluster). Protons (+ charge) Neutrons (no charge) Electrons (- charge)

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved The two electrons are in the same shell even though they have different orbital paths. HELIUM ATOM + - = Neutron = Proton = Electron

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved = Neutron = Proton = Electron Each electron stays in its own orbital path. HELIUM ATOM

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved = Neutron = Proton = Electron Each electron stays in its own orbital path. HELIUM ATOM

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved = Neutron = Proton = Electron Each electron stays in its own orbital path. HELIUM ATOM

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved = Neutron = Proton = Electron Each electron stays in its own orbital path. HELIUM ATOM

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved = Neutron = Proton = Electron Each electron stays in its own orbital path. HELIUM ATOM

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved = Neutron = Proton = Electron Each electron stays in its own orbital path. HELIUM ATOM

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved = Neutron = Proton = Electron Each electron stays in its own orbital path. HELIUM ATOM

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved = Neutron = Proton = Electron Each electron stays in its own orbital path. HELIUM ATOM

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved Concept Preview Electrons are always in motion. Electrons and protons have an electric charge. Atoms contain electrons, protons, and neutrons. Repeat Segment

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved Formation Of Ions from Atoms

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved Concept Preview Ions are basically charged atoms. A negative ion has gained an electron. A positive ion has given up

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved A SODIUM ATOM

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved AND A CHLORINE ATOM

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved Sodium Atom - FORMATION OF IONS Chlorine Atom

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved Sodium Ion - Free Electron FORMATION OF IONS Chlorine Atom

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved Chlorine Atom Sodium Ion - FORMATION OF IONS

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved FORMATION OF IONS Chlorine Atom Sodium Ion -

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved FORMATION OF IONS Chlorine Ion Sodium Ion -

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved Concept Review Ions are basically charged atoms. A negative ion has gained an electron. A positive ion has given up Repeat Segment

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved Static Charges

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved Concept Preview An attracting force exists between unlike charges. two like charges. A repelling force exists between Positively-charged objects have a deficiency of electrons.

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved _ charge _ _ _ _ Like charges produce a repelling force. When physically released, they repel each other. Force Between Electric Charges

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved Charged rod. (Many negative charges have been removed from the rod.)

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved _ +_ +_ +_+_+_+ +_+_ Uncharged ball suspended on a thread. (Equal number of negative and positive charges uniformly distributed.)

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved _ +_ _ +++_+_ _ +_+_ Ball receives small induced charge as rod approaches. (Note clustering of like charges on ball’s surface.) Weak force of attraction develops.

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved _ _ _ + +_ _ More clustering of like charges and stronger attraction occurs as the rod is moved closer to the ball.

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved Electrons are transferred from ball to rod when contact is made. Now, both ball and rod have a positive charge.

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved The ball is now repelled by the rod because of the like charges on the two objects.

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved CHARGE QUIZ Electrons have a _____ electric charge.negative Protons have a _____ electric charge.positive The _____ is electrically neutral. neutron The charge of a sodium ion is _____. positive A chlorine ion has a(n) _____ of electrons.excess Like charges _____ each other.repel

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved Concept Review An attracting force exists between unlike charges. two like charges. A repelling force exists between Positively-charged objects have a deficiency of electrons. Repeat Segment

McGraw-Hill © 2013 The McGraw-Hill Companies Inc. All rights reserved REVIEW Work and Energy Atoms Ions Charge