concept test
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Name Name Physics 132 Quiz # 13 1.1. Car Carbatteries batteriescan canbe berated ratedininampere-hours ampere-hours(A.h). (A.h). What Whataspect aspectof ofthe thebattery batteryisisbeing beingrated? rated? A.) A.) Their Theirpeak peakcurrent current B.) B.) Their Theirmaximum maximumpower power C.) C.) The Thetotal totalcharge chargethey theycan candeliver deliver 2.2. Two Twoidentical identicalresistors resistorsare areconnected connectedfirst firstinin parallel, parallel,and andthen thenininseries. series.Their Theirtotal total resistance resistance ininthe theparallel parallelconfiguration configurationisisRRpp, ,and andininthe theseries series configuration is configurationisisRRs.s.The Theratio ratioRRs/R s/Rpp is A.) 11 A.) B.) 22 B.) C.) 33 C.) D.) 44 D.) LECTURE 14 Concepts Concepts & & Topics Topics •• •• Energy Energy in in Electric Electric Circuits Circuits Combination Combination of of resistors resistors Energy Dissipated in Electric Circuits ∆U = ∆Q(V2 −V1) = −∆QV ∆U ∆Q P = − = V = IV ∆t ∆t (a) (b) V=const I=const intensity intensity EXERCISE EXERCISE AAlight lightbulb bulbwith withvariable variable resistance resistanceRRisisfirst firstconnected connectedto toaavoltage voltage source source(V=const.) (V=const.)and andthen thento toaacurrent currentsource source (I=const.). (I=const.).Sketch Sketchthe thelight lightintensity intensityas asaa function functionof ofR. R. (note: (note:the thelight lightintensity intensityisis proportional proportional to tothe thedissipated dissipatedpower.) power.) I= oonst. R V= oonst. R Energy Dissipated in Electric Circuits CONCEPT TEST: TEST: CONCEPT Twoidentical identicallight lightbulbs bulbs AAand andBBare are wired wired Two inseries seriesand andconnected connectedto toaapower powersupply, supply,as as in shownin inthe thefigure. figure.Which Whichone oneisisbrighter: brighter: shown 1.1. AA 2. B. B. 2. Theyare arethe thesame. same. 3.3.They A B + - CONCEPT TEST: TEST: CONCEPT Four identical identicallight lightbulbs bulbsare are wired wired Four inseries seriesand andin inparallel parallel,,and andthen thenconnected connected in toidentical identicalpower powersupplies, supplies,as asshown shownin inthe the to figure.Which Whichcircuit circuitemits emitsmore morelight light figure. Theseries seriesconfiguration configuration 1.1. The Theparallel parallelconfiguration configuration 2.2. The Theyare arethe thesame. same. 3.3. They +V - + V - Combination of resistors Resistors in Series CONCEPT TEST: TEST:Two Twoidentical identicalresistors resistors CONCEPT arewired wiredin inseries. series.The Thecurrent currentin inthe thesecond second are resistorisis resistor equalto to 1.1. equal 2. half halfof, of, 2. Smallerthen, then,but butnot notnecessarily necessarilyhalf halfof of 3.3. Smaller thecurrent currentin inthe thefirst firstresistor. resistor. the Combination of resistors Resistors in Parallel CONCEPT TEST: TEST:As Asmore moreand andmore moreresistors resistors CONCEPT areadded addedto tothe theparallel parallelcircuit circuitshown shownhere, here, are thetotal totalresistance resistancebetween betweenpoints pointsPPand andQQ the Increases. 1.1. Increases. remainsthe thesame. same. 2.2. remains 3. Decreases. Decreases. 3. P Q Combination of resistors CONCEPT TEST: TEST: CONCEPT Three identical identicallight lightbulbs bulbs A, A,BBand andCC Three are wired wiredas asshown shownin inthe thefigure. figure.The The are brightnessof ofBBand andCCtogether, together,compared comparedto to brightness thebrightness brightnessof ofAAisis the 1.1. 2.2. 3.3. Twiceas asmuch much Twice Thesame same The Halfas asmuch much Half + V - Sample SampleProblem ProblemFor Forthe theresistance resistancenetwork network shown shownin inthe thefigure figure (a) (a) First Firstchoose chooseRR11==44Ω, Ω, RR22==66Ω. Ω. Find FindRR33 such such that thatRRabab==RR11.. (b) (b)Now Nowchoose chooseRR11==44Ω, Ω, RR33==33Ω. Ω.Find FindRR22 such such that thatRRabab==RR33..
