questions-39-41-refer-to-the-following-figure-figure-cannot-copy-if-v100-mathrmv-r_150-omega-r_280-o

Question

Questions 39-41 refer to the following figure:
FIGURE CANNOT COPY
If $V=100 \mathrm{V}, R_{1}=50 \Omega, R_{2}=80 \Omega$ and $R_{3}=120 \Omega,$ determine the voltage across $R_{3}$ .
(A) 100 V
(B) 60 V
(C) 40 V
(D) 20 V

Vishal Gupta · Accepted Answer

Hi in the given problem. The two resistors R two and R three first of all are in series then. But resistor R one is in parallel with these two. This combination is connected, yep. A source of voltage providing voltage. V The value of this week is 100 world resistance are one is 50 oh R two is mhm. Be home and our three is 120 no. As voltage remains seen in parallel. So the series combination of R. one and R two will get seen. We is equal 200 walls across them. Therefore current passing through them will be given by Homes Law as I used to be by our for our disease are too plus our three the net resistance in serious combinations. So here it will be underworld divided by 80 Last 120 mm. Yes this is hunted by 200 or we can say current passing through the city&#x27;s combination A 0.5 and here now as current remains the same in series. So the current across this artery will also be seen 0.5 Ampere. Hence voltage drop a cruise. Our three will be using arms law again. That will be given by I into our This is I into our three For either 0.5 and pure multiplied by our three 120 home. So finally this voltage here comes out to be 60 world. Hence we can say, yeah, our option B is correct. Yeah. Thank you.

Ze-Han Lee · Answer

So we have the circuit, aren&#x27;t one, are two and our three okay are wise. Ah, 50 olds are too is Ah, 80 homes and our three is Ah 1 20 homes. Right? And V is Ah, 100 volts. So I want to find out the voting across our three. So we first begun. Determine the current through this French Simply quit to I quote VD Bye bye. Are two plus our three, right? So this gives you 0.5 years. So the voting across all three will be good to re three equal. I times are three. So which gives you 60 volts?

Benjamin Arndell · Answer

Hello and welcome to Chapter 18. Problem number 26 of Holt Physics. So this is a very large circuitry problem with multiple different resistors. I&#x27;ve written them here as resisters one through seven for our notation later on, um, and the actual values over here on the side. I&#x27;m sorry for the the amount of space here. It&#x27;s Ah, I promise you are. Seven is down there, and so is our voltage here. Um, so first thing we need to do is find the equivalent resistors resistance of all of our resistors here. And we do that in order to find the total current going through our entire circuit. So start things off. We&#x27;re going to look at these peril. These resistors in parallel. Remember that. Use resistors in parallel, add reciprocally. So have the calculations down here, and they actually turn out to both be ah, three when you do the math to six. Sorry to six. And then foreign 12. Uh, so they we have three owns their onda. Next up, we&#x27;re going to redraw our circuit just for clarity&#x27;s sake. So now we have ah, circuit. That looks a little bit like this guy on the left here and I also have written over here points A, B, C and D. Those are come important a little bit later on in our problem here, but just keep that in mind. So now we have another set of parallels and another set of Siri&#x27;s. So I just added them really quick over here. Three plus three and three plus two. I assume you guys could do that s we&#x27;ll have six and five and then this third the last resistor here that&#x27;s untouched. And now, if you notice that point d is gone, so we&#x27;ll just have a B and C. And now the last equivalent resistance that I really need to do a calculation of is I just have it over here to the right. We have a six plus 1/5 that&#x27;s gonna give us when you do the reciprocal, it&#x27;s going to give us 30/11. A six plus of fifth is 11/30. We flip it so ah, 30/11. I have it as a fraction here, but I&#x27;m gonna quickly convert it to a decimal in the next step here. So we have 2.72 That&#x27;s what sorry, that&#x27;s what that&#x27;s gonna be. When you do it as a decimal on DA, it&#x27;s gonna 2.72 repeating. But whatever, um and so that, along with our three ohm resistor, will give us a total resistance are equivalent resistance for our entire circuit of only about 5.72 owns, which is kind of small if you look at back at the original problem. But that&#x27;s fine. It&#x27;s That&#x27;s why resistors in parallel exists. It&#x27;s it&#x27;s interesting. Um, so now we can finally use OEMs law to find our total current running through our entire circuit vehicles ir isolate for I using are given voltage of 18 volts and our final resistance here. We have a cute little number here pie, and we have 3.14 amps. But that&#x27;s, you know, side note. Um, so next up we need to dio is we can actually finally start solving our problem. Um, the first part. So we need to go back to those points B and C here. We need to have the vote the voltage difference across that. So let&#x27;s go back up here and look at B and C. So it&#x27;s going to be the voltage across these two. Because remember, these two resistors are in parallel, so they have the same voltage. And that&#x27;s going to be that 2.72 OEMs. Remember? That&#x27;s why it&#x27;s over here. So we&#x27;re gonna use the voltage 18 owns. Oh, sorry. Uh, down here, we&#x27;re gonna use our, um our total current that we calculated the 3.14 amps times the resistance of point between points B and C&#x27;s. That&#x27;s our 2.72 and 3.14 and will have, ah, voltage difference of 8.55 And that&#x27;s just across this point here. BNC. So these guys thes two resistors share that voltage Now we can finally dio, uh, we&#x27;re pretty much done with all of her initial set up. We can start doing a through D on the actual problem here. So it&#x27;s pretty. It&#x27;s pretty straightforward once we have all of our values. So we have next we need to find the current, uh, through points, B, D and C. I&#x27;ll go back up just so we can see we&#x27;ve been very clear where that is. We have points B, D and C so We have the current from this right afterwards, Uh, three ohm resistor, The current that goes on this branch on the bottom here. Okay, so over down here doesn&#x27;t matter. Eso we do that by doing our voltage from BC that we calculated 8.55 times that resistance from BC, which is five. I&#x27;ll go back up one more time, I promise. Won&#x27;t be sickeningly changing, but be to see here we have that five home. There was the three homes plus two homes from this side. All right, and so that will actually give us our first problem. A first answer. We have 1.7 amps going through points be DNC the next problem. Next point, the property is asking us to find the voltage across that two ohm resistor ago. Bahamas allied, actually go back way to the top. The vultures across this two ohm resistor. Um, way up top Here. We have this to ome. Sorry. This to own guy right here. Voltage across this, this bad boy right here. And so in order to do that, we actually used the answer from part A. The current because that was going through b d and C times that to own resistance. All right, so that&#x27;s gonna give us 3.4 volts. And now we know the voltage across. I have to go back up every time. I&#x27;m sorry, guys. Um, we&#x27;re gonna know the voltage across this thing here because we went through. This is if you look back, this is really be d and C right here. So that&#x27;s what we use that current going to this bottom half The branch there is now I know the voltage across here. So next up, it&#x27;s asking us to find the voltage. Sorry. We&#x27;re looking for the voltage across that 12 ohm resistor, which was, if you remember, it was the bottom half of the bottom branch. We got that out. It was I believe it was our four in my original schematic. So we&#x27;re gonna use this. Ah, voltage that we got from the first part. Um minor. There. Voltage from BC, which we got actually very right before we started any of this solving this BC voltage here, 8.55 minus the voltage from the two ohm resistor. Right, So we&#x27;re gonna keep going back up, so we&#x27;re gonna It&#x27;s basically the voltage across from this strip here, minus this strip here. All right, so when we do that, we&#x27;ll get our final answer of 5.15 volts, and we&#x27;re almost done. Now, the final part is asking us the current through that, uh, that 12 ohm resistor itself. And so, thank God we just got that voltage BC, Um, are that voltage from the 12 home? And we have We know what the 12 1 resistors resistance is. So we just do it more almost Law. And we have 5.1 5/12 to give us 0.43 amps, and that&#x27;ll do it for this problem.

Jayashree Behera · Answer

so digital. Mind the current flowing through our tree to be equal to two ampere. Now again, we can use onslaught to find the world. It&#x27;s drop across on tree blooms. Losses that is equal to times are so we can find the world is dropped across Artie by using this equation. So we have to UN beer, which is the current going through the resistor on the value off the resistance. Just one. And this gives the world its drop to be Duval&#x27;s. So the correct answer is going to be option a.

Manish Haldankar · Answer

in this particular some, we need to find the violent resistance on current to each register for three different cases. So let&#x27;s start with Step A here, here when five week battery is connected between and B. So let&#x27;s attach a battery first withdrawal. So good. Daggett. I&#x27;m here. Is going to be 100 homes next, 0.1 over a distance with one home and dinner. No, these are the two different nose A and B, and we need to apply off. I went back through here, you know, the same could influence through one of 10 on 100 because they are connected. E series. So what we&#x27;re going to right here seem didn&#x27;t fills two. Why no general and 100. Therefore, let&#x27;s take the notation as rs. So one less day last 100 homes, that is 111 norms, which is the value of artists. I would like to make a diagram again so that that it will be clear and miss standing what you&#x27;re doing exactly. So get a five word about three attach between A and B. This is our 0.1 home, and again the same thing as we can see here between a Toby, This is gonna be a There&#x27;s gonna be big Ari&#x27;s is connected now that gun and which would be flowing through this tour distances that&#x27;s considered as Ivan and I do. So now we need to find our equivalent. So are equivalent in this case will be since this tour, the distances point with him. 111 home. I didn&#x27;t battle it. We can can&#x27;t really there. So let&#x27;s go to the next page. So therefore, article violent is equal to zero point. Come on, monkey Bribe 100 even upon edition off too. It could give us a value. As you know, porn 099 homes. This is the first answer that we have Court. Let&#x27;s mark this. This is what we need to find out next. In the same case, we need to find Ivan the night to values. So we&#x27;re right down to calculate gotten two each register Ivan is equal to since file Isn&#x27;t balladry board their distances simply politically? Using No Mr Ivan is equal to or dish upon resistance. So far, I divided by zero point. Welcome. We&#x27;re just coming as 50 amperes. And in order to calculate the value of I do it would be five point do. I did about 100. Any Lebanon which is going to be zero for zero Full fire appears. Now if you have got to second answer. No. Thus begins right here. That is current to Ottoman is equal to island is equal proof of camp years. And I didn&#x27;t two. Why No Daniel and 100 home is equal to I go is equal to 0.45 amperes. We can write this in the district. Go away like this. No. Next move, four step. Be right here. Now we&#x27;ll think about step be here. The case is being a five. Word is a bash between Hey and see So let&#x27;s make the diagram First 100! Oh, and we have treated the senses now going to him one and 10. Boom! 0.1 one Home and Daniel. The points are you can see right here. This is gonna be This is C asper given in the original diagram. And this is war to be a good girl Attach, which is five work. So now let&#x27;s consider that that&#x27;s tagged In addition off artist one and ours too So this one is. It is a city&#x27;s combination of 0.1 anyone. So which is 1.1? No artist, too, is the city&#x27;s combination off other great distances. That is, Stan last 100 on which is 100 down. So let&#x27;s make the diagram first, and it is going to be something like this. So this is artist one, and that is to artist. One is 1.1 artist. Do what we have got as 110 holes on the terminals are connected to pay and see, nor with fine words are dashed. So now that&#x27;s mentioned. The garden says, Well, this is gonna be Ivan, and let&#x27;s assume it as I do. So if you want to calculate, dig around in the distant, these two resistance is now in pattern because main current I is grating speeder into two components. That means the distances are said to be in balance. It&#x27;s moving in a speech, and so this are equivalent is equal to honest one battling to arrest you. Now the values er artist one value is 1.1 home about it 200 down. It&#x27;s got a great dis using the Formula 1.1 might be player 110 you&#x27;ve I D to buy, and you should, too, which is equal to one corn, 089 elms. This is the value of our equivalent in case be that we have. It&#x27;s market as one of dancers now greed rather to find God and to each register. So Ben Boyd Ivan Ivan isn&#x27;t currently just flowing to 1.21 So what we do? Five World divided by artist one, which is equal to five old, divided by 1.1 home, which is equal to four point fi wolf I on beers. Let&#x27;s stick. I do, I do. If I were divided by artist, too, which is equal to five world divided by 100 dams, which is equal to legal 0.0 full 55 Amperes I d. Answers that we have got. Now we need to write down descriptively does. I couldn&#x27;t two. I see your 0.2 on and one on is equal to Ivan, which is equal to 4.5 for five years, and the 2nd 1 is current. Two. Jay No and 100. Home is equal to Idaho, which is equal to 0.4 55 amperes. This is what we can mention your escape before. No, let&#x27;s go to the next beach. You start. It&#x27;s tipsy. In this case, five words is a dashed between E. Andy. No, that&#x27;s stronger. Diagram. Again, this is gonna be the same. That his 100? No, right at the boredom. 32 distances at a connector. That&#x27;s where the original diagram Jeff going, going, going home. I&#x27;m taking off. Attach a battery off firework Do the terminus E as villas. Andi. So it is going to be C I run and it is going to be I do now. Here, let&#x27;s start again. It&#x27;s stick artist one artist one. We&#x27;re considering the combination off 0.1 less one last stand So the same gun flows garden cities. So once we can create this, we get at least one as 11.1. Now let&#x27;s talk about our equivalent. Casper. The question now this 100 own is in battle with this one, which is 11.1 that&#x27;s got over 800 multiplied by 11.1 upon again. Addition off, too. So which is ultimately coming as 9.99 homes. We could get you and Vicky does Daniel mes. I&#x27;ll keep the original figure, Aditi&#x27;s, which is one of dancers. Let&#x27;s go next. Therefore, it&#x27;s comfort Ivan, since this combination is in battle. Fly void. Do I do about this one? So five Ward do. I did buy in a 1.1 so on Sin is coming as zero boring for five years. Similarly, to get the value of I do okay, five World divided by 100 homes. It is coming at a 0.5 years. Again, this is the next census said that we&#x27;ve got to write in a distributor for Matt and does couldn&#x27;t two zero point Do I know why No and General is equal to liven statistical to 0.45 years and next is current two 100 0 is equal to ICU because equal to 0.5 amperes, this is the way we can write. Go and sit in the descriptive format

Luis Rios · Answer

so the goal of this problem to calculate the voltage that different volt meters will read when attached to the 30 k resistor. And we know that volt meters have to be attached in parallel with the resistor in order to get a reading in part A. That internal resistance of the Volt meter It&#x27;s 50,000 Holmes and since we know they&#x27;re connected in parallel to the 30 K let&#x27;s find the resistance between those two. So in order to do that, we use the equation. Form two parallel resistors. R One times are too divided by R one plus to so are one will be the 30 k You just there are to 50 k divided by R. One R two is 80 k so there total resistance is 1.88 Tend to the fourth. Now let&#x27;s look at the other side of the circuit with this 40 k and this 40 k resist. There are, and they&#x27;re also in parallel with each other. Well, let&#x27;s find their combined resistance. It&#x27;s a R P is equal to 40 k time for the king. A lot of my 40 k plus 40 K&#x27;s again 80 k so they&#x27;re combined. Resistance is simply too times 10 to the fourth Holmes. So now we have two resistors that are now in Siris with one another so we can find the are equivalents as 1.88 times 10 to the fourth Mr First Resistor, plus two times since fourth. So the combined resistance of entire circuit is three point. I need eight. Thanks. 10 to the fourth Holmes. Now we can find the current of the entire circuit since we know the voltage of the battery, which is 100 volts. And we know that current I is equal to the voltage provided by the resistance so clogging our numbers. 100 volts get better buying 3.8 times 10 to the fourth. And so the current of the circuit is 0.25 amps. So, no, we can use this current to find the voltage that the vote beautiful read at the 30 k resistor. So we know from homes law voltage is equal to the current time. The resistance. Well, the current we just found, which is 0.0 25 times a combined resistance of the volt meter in the 30 K which we said was 1.88 has 10 to the fourth. And so the voltage that the vote mineral read with the third with the 50 k internal resistance is V is equal to 48 52 votes, not for part B. The internal resistance of of the second volt meter is 250 k Holmes. So if you go back to the problem, the 40 k resistors stay the same, so their equivalent resistance stay the same. So the only thing that changes is a combined resistance of a volt meter with the 30 k so you can go back to using this equation but replaced the 50 k with the 2 50 k So r P 30 k times 2 50 k divided by 30 camp was 2 50 k and 280. Okay, it&#x27;s another combined resistance is 2.67 attempting to the fourth homes and again, this is in serious with the combination of the 40 k resistors. So there are equivalents, or the total current, or a total resistance of entire circuit is two point 67 10 to 4, close to for the fourth the total resistance. It&#x27;s four point 67 I understand to the fourth home and again confined current of the circuit with this new resistance. So it&#x27;s 100 you better by 4.67 times 10 in the fourth. So the current now flowing to the circuit 0.0 to 1 ham&#x27;s and again we can find the voltage. The volt meter will indeed, with this current so 0.0 0 to 1 times 2.67 times 10 to the fourth to the combined resistance of the volt meter. And the 30 came your sister. So now, for part B, the voltage is 56 0.7 volts. No, part c is essentially the same thing. The same procedure only that the internal resistance is now 10 mega homes or 10 times 10 times 10 to the six. So again we use going back this equation now we replaced the 2 50 came with 10 times 10 to the sixth resistor. So you have R P? Yes, he could do that. 30 cane since Tim make a home they wanted by the 30 King plus 10 mega. So now the resistance is 2.99 10 to the fourth. And then we add that to the combination of the 40 cave resistors. So are equivalents is 2.99 times 10 to the fourth, plus two times 10 to the floor. So we&#x27;re left with 4.99 times 10 to the fourth Holmes the total resistance of the entire circuit. And now again you confined the current so voltage divider by the are equivalent So 100 divided by 4.99 that&#x27;s 10. 34th. So the current flowing through the circuit this 0.2 naps Now again, we can find the voltage is that the volt meter will read so often is equal to the current times resistance 00 to times the combination of the 10 mega and the 30 k resistor two point anything Cumpston to the fourth. So the vote meaner read the is equal to 59 0.91 Holtz

Problem

Questions 39-41 refer to the following figure: F…

Problem 40 Easy Difficulty

Questions 39-41 refer to the following figure:
FIGURE CANNOT COPY
If $V=100 \mathrm{V}, R_{1}=50 \Omega, R_{2}=80 \Omega$ and $R_{3}=120 \Omega,$ determine the voltage across $R_{3}$ .
(A) 100 V
(B) 60 V
(C) 40 V
(D) 20 V

Answer

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