a) What is the potential difference between points a and d in Fig. 19–57 (similar to Fig. 19–13, Example 19–8), and b) what is the terminal voltage of each battery?

a) V_{da} = 34 V b) V_{T1} = 82 V, V_{T2} = 43 V

Giancoli 7th Edition, Chapter 19, Problem 29

Problem 29

What is the potential difference between points a and d in Fig. 19–57 (similar to Fig. 19–13, Example 19–8), and
what is the terminal voltage of each battery?

Figure 19-57.

Figure 19-13 Currents can be calculated using Kirchhoff’s rules. See Example 19–8.

$V_{da} = 34 \textrm{ V}$
$V_{T1} = 82 \textrm{ V, } V_{T2} = 43 \textrm{ V}$

Giancoli 7th Edition, Chapter 19, Problem 29 solution video poster

In order to watch this solution you need to have a subscription.

Get Started

View sample solution

COMMENTS

By ctlawson on Wed, 2/10/2016 - 12:49 PM

Hello,

At 6:09, you added 1.3235 and 6.8421 to get 8.1556 and then you added -1.4118 to -2.5263 to get 4.9381. Should you have gotten 3.9381(I3)=8.1656 instead?
Thanks in advance for your help.

By Mr. Dychko on Wed, 2/10/2016 - 6:44 PM

Hi ctlawson, thanks for the question. At 6:09 two things were done at once: $-1.4118I_3 - 2.5263I_3 = -3.9381I_3$ as you say, but the second thing done is that this quantity was moved to the other side of the equation. There is the term $1I_3$ over there, so the result is $1I_3 + 3.91381I_3 = 4.91381I_3$ on the left side.

Hope that helps, and all the best with your studies,
Mr. Dychko

By ctlawson on Thu, 2/11/2016 - 11:03 AM

Oh, I see now. Thanks for your help.

By chuy4espindola4 on Wed, 3/9/2016 - 4:51 PM

How does the -2.5263 I3 added to the -1.4118 I3 equal 4.981 I3? Should it not be 3.981 I3?

By Mr. Dychko on Thu, 3/10/2016 - 4:47 AM

Hi chuy4espindola4, that's a good question. Another student also asked about that step, and here was my reply: https://www.giancolianswers.com/giancoli-physics-7th-edition-solutions/…. Please just ask further if something there isn't clear.

All the best,
Mr. Dychko

By pansapinsa on Mon, 8/22/2022 - 2:33 AM

Is this typical for such problems to be this confusing with the direction of the current? I spent so much time redoing my math, trying to figure out what I was doing wrong... Honestly, if they did not provide any direction of the current at all, it would be better...

Find us on: