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Both batteries in Fig. 27-43a are ideal. Emf ℰ1 of battery 1 has a fixed value, but emf ℰ2 of battery 2 can be varied between 1.0 V and 10 V. The plots in Fig. 27-43b give the currents through the two batteries as a function of ℰ2. The vertical scale is set by is = 0.20 A. You must decide which plot corresponds to which battery, but for both plots, a negative current occurs when the direction of the current through the battery is opposite the direction of that battery’s emf. What are (a) emf ℰ1 (b) resistance R1, and (c) resistance R2?
Figure 27-43 Problem 32.
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