College Physics

Figure 21.4(a) Three resistors connected in parallel to a battery and the equivalent single or parallel resistance. (b) Electric ...

Example 21.2 Calculating Resistance, Current, Power Dissipation, and Power Output: Analysis of a Parallel Circuit Let the voltag ...

(21.30) P 2 =V 2 R 2 = (12.0 V) 2 6.00 Ω = 24.0 W and (21.31) P 3 =V 2 R 3 = (12.0 V)^2 13.0 Ω = 11.1 W. Discussion for (d) The ...

motor and a passenger compartment light. We have previously assumed that wire resistance is negligible, but, when it is not, it ...

Vp=V−V 1 = 12.0 V − 2.35 V = 9.65 V. (21.41) Now the currentI 2 through resistanceR 2 is found using Ohm’s law: (21.42) I 2 = Vp ...

Use the appropriate list of major features for series or parallel connections to solve for the unknowns. There is one list for ...

Figure 21.9Any voltage source (in this case, a carbon-zinc dry cell) has an emf related to its source of potential difference, a ...

Why are the chemicals able to produce a unique potential difference? Quantum mechanical descriptions of molecules, which take in ...

Similarly, withRload= 0.500 Ω, the current is (21.48) I= emf Rload+r = 12.0 V 0.600 Ω = 20.0 A. The terminal voltage is now V = ...

Figure 21.14A car battery charger reverses the normal direction of current through a battery, reversing its chemical reaction an ...

Figure 21.17These two voltage sources are connected in series with their emfs in opposition. Current flows in the direction of t ...

Animals as Electrical Detectors A number of animals both produce and detect electrical signals. Fish, sharks, platypuses, and ec ...

Figure 21.21This circuit cannot be reduced to a combination of series and parallel connections. Kirchhoff’s rules, special appli ...

Kirchhoff’s second rule requiresemf −Ir−IR 1 −IR 2 = 0. Rearranged, this isemf =Ir+IR 1 +IR 2 , which means the emf equals the s ...

Example 21.5 Calculating Current: Using Kirchhoff’s Rules Find the currents flowing in the circuit inFigure 21.25. Figure 21.25T ...

Substituting these two new equations into the first one allows us to find a value forI 1 : I 1 =I 2 +I 3 = (6 − 2I 1 ) + (22.5 − ...

Figure 21.26The fuel and temperature gauges (far right and far left, respectively) in this 1996 Volkswagen are voltmeters that r ...

Figure 21.28An ammeter (A) is placed in series to measure current. All of the current in this circuit flows through the meter. T ...

Figure 21.30A small shunt resistanceRplaced in parallel with a galvanometer G produces an ammeter, the full-scale deflection of ...

arbitrarily small. This actually limits knowledge of the system—even limiting what nature can know about itself. We shall see pr ...