Resistors Definition and 598 Threads

Homework Statement "What is current flowing through R4?" Hope you're able to see the diagram I attached, any help would be awesome, I'm really quite confused.

Hey, this is my first post ever on PF, and I have done my best to follow the guidelines on posts asking for help with homework. Please know that I am not after the answer just to cheat and get the questions right, I am after the method so that I could do a similar question myself in the future...

Just wondering how my Ohms/Watts should my bleeder resistors be on a cap bank ratted for 1000v at 1620 microfarads (Each cap is 200v at 2700 microfarads) so a total of 810 joules if I'm not mistaken. (5 caps in series and 3 strings) |[]-[]-[]-[]-[]| |[]-[]-[]-[]-[]|...

Homework Statement A circuit with one 5V and 3 resistors in parallel. What is the voltage across one of the resistors? Homework Equations V=IR The Attempt at a Solution 5/3 V?? or should i put R1 = 5V/I -R2-R3 V how do we get voltage across one of the resistors without...

what are pull up and pull down resistors i read that i have to connect pull up resistors with microcontroller why they are called pull up resistors and not simple resistors?

Homework Statement Two 9.4 k-ohm resistors are placed in series and connected to a battery. A voltmeter of sensitivity 1000 ohm/V is on the 3-V scale and reads 2 V when placed across either resistor. What is the emf of the battery? (Ignore it's internal resistance) Homework Equations...

Hi guys, I have an interesting and difficult problem as follow: Find the smallest number of 12 Ohm resistors (and of course how to connect them) to achieve an equivalent resistor of 7.5 Ohm? I have worked on this problem for many hours but cannot find the answer yet. Somebody can...

Not sure whether to post in mathematics or physics section. A circuit contains a cell of unit E.M.F. Use any combination of identical resistors in series and/or parrallel in order to create a voltage of x across a voltmeter connected anywhere on the circuit. Assume that there is no internal...

there are 3 resistors of, different values. 470o,22o and 100o. but each one is 500W I want to connect them in series/parallel in order to dissipate the maximum power 500W. I have connected 4,22o in series and 2, 100o in series, 1, 470 in parallel. but the dissipation is not maximum. the...

I have a string of leds hooked up together with the correct resistors in parallel, going out to a TIP31 transistor which then goes to the power cord and to a 3mm jack. This 3mm jack goes into my computer and my leds "dance" to the music, I assume is the change in voltage. Anyways, I have...

Homework Statement Two resistors with R1 = 1755 omega and R2 = 4020 omega are connected in parallel. The battery emf is large epsilon = 15 V. What is the current through resistors R1? What is the current through resistors R2? Homework Equations The Attempt at a Solution I...

Hello. my robot requires an 18k resistor at one point. my problem is that I don't have one and my radioshack has never heard of it. anyway, I was wondering on how to create one. I know that adding in a series circuit it's just R1+R2... and I think that parallel circuits add with the...

1. what is the Electric current that goes through the ampermeter (see the picture) http://imageshack.us/photo/my-images/545/66683625.png" [PLAIN]http://img545.imageshack.us/img545/4379/66683625.png 2. the current that goes through the 2R resistor is \frac{4\epsilon}{13R}. (I dident...

I have a comparator ckt with external hysteresis. When I apply a square wave input everything works fine. The trip points are as designed, output goes high/low etc. But when I increase the duty cycle of the square wave to say beyond 75%, the output just stays high. I was playing with the...

Homework Statement The components of a circuit with a voltage source and 2 resistors ( series ) has the following values vs = 10V, R1 = 100 , R2 = 150. With i1 leaving the +ve vs and i2 leaving -ve vs ( i.e. i1 entering node A, i2 is entering in the opposite direction of i1 ) Find: a)...

Homework Statement It's only one question. How to transform this ciruit to only one resistor? Homework Equations The Attempt at a Solution

Hello, I was wondering if someone here could confirm or explain what happens in a resistor. My assumption is that when the electrons enter a resistor, they slow down, thus decreasing the strength of the electromagnetic field and causing the excess energy the field can no longer hold to be...

I looked this up, and found that it limits the current going through, but say if we have a c ircuit with a power source and 1 resistor, the current through the resistor is the current coming out of the resistor. I know if you hook the resistor up in parallel that is not the case, but in some...

Is there some good way to make 109 to 1012 ohm range resistors? (buying them is expensive). I've been experimenting with pencil traces on paper, that is understandably unstable, going to try with pencil traces on the ceramics then cover it with glue. I was wondering if there's some well known...

I know that in the left circuit, current will not flow where the resistors are attached to the straight wire connecting A and B, but on the right one, current will flow where the resistors are attached to the straight wire x and y http://img824.imageshack.us/img824/880/this1p.jpg Is...

[b]1. Homework Statement [/b I have been asked to find the equivalent resistance for the given attachment. Homework Equations first, i solved the parallel connection and the answer is 11K and now this 11K in series with 27K, so the answer is 38K Am i right? The Attempt at a Solution

We did a lab with decade resistance boxes. We had to set up three boxes of the same resistance in parallel. However, I am confused as to how to connect the cords. We used an ammeter to measure the current and a dc voltage machine. Can someone please show a diagram on how to hook up the boxes...

The problem is: Three 5 ohm resistors are each rated at 10 watts. What is the max voltage that can be applied if they are connected in a: series b: parallel I know the properties for adding up resistors in parallel and series but how do you incorporate the 10 watts for each of the...

Please see attachment for the problem. I used the rules for parallel and series resistors to find a total resistance in the network of 4560/59 ohms and then found a current of 59/152 amps through the 20 ohm resistor in the original problem. Am I correct?

Homework Statement Give the features and the utilities of the series and parallel combination of resistors. The Attempt at a Solution Series combination:- (i)The current has a single path for its flow.Hence the same current passes through each resistor and so the potential difference...

resistors and currents--circuits Homework Statement What is the current through the 10 ohm resistor in the figure ? Homework Equations V=IR The Attempt at a Solution Am I supposed to use Kirchhoff's loop law? I think I have too much info. to use that. But I think the current...

Homework Statement Hello. I am having trouble understanding the simple circuit diagram that is attached. I need to explain what the function of the two resistors are. I know some basic things about circuits (Ohms law, Kirchoffs loop rules,etc.) but I do not know exactly how a vacuum tube...

Homework Statement http://img97.imageshack.us/i/physicsquestion.png/ Homework Equations R= V/I For Series: R[SIZE="2"]eq= R1+R2 For Parallel: 1/R[SIZE="2"]eq= 1/R1+1/R2The Attempt at a Solution I have two attempts remaining for each question

Homework Statement Consider the circuit shown in the Figure, where R1 = 29 and R2 = 4.8 . http://www.webassign.net/walker/21-44alt.gif (a) Is the current flowing through the battery immediately after the switch is closed greater than, less than, or the same as the current flowing...

1) Using Ohm's Law determine the eqv resistance across the battery. 2) Determine the currents through all resistors

Homework Statement Two resistors, 16.0 Ohms and 20.0 Ohms are placed in parallel with a 12 V source. Homework Equations What is the total current from the source and what is the power dissipated in each resistor? The Attempt at a Solution Req=(16*20)/(16+20) = 8.88 Ohms V=Req*I...

I was reading through my circuits book for a beginning EE course and the book was going over troubleshooting open resistors for resistors in series. I understand that no current will be measured across the resistor because the current path has been cut off. I don't understand how the full...

Homework Statement Two identical long bulbs are wired in series and connected to a 4.5-volt battery pack. The resistance of each bulb is 50 ohms. a. Determine the voltage across each bulb. b. Determine current through each bulb. c. How does this compare to the current flowing out of...

Homework Statement In the figure below, find the following. (Let E1 = 26.0 V, E2 = 13.0 V, and R = 9.0 Ω.) (attachment) (a) the current in each resistor I1 = I2 = I3 = (b) the power delivered to each resistor P1 = P2 = P3 = Homework Equations V=IR...

Hey everybody, I’m taking a class in switching theory, and am having a little trouble with a theoretical review question. There is a schematic, but I feel it’s unnecessary (and I don’t know how to post it.) We have 2 inputs to a circuit, A and B. 3 combinations stem from this. A’B, A’B’...

Homework Statement Find the current through all resistors. Find the potential difference across all resistors Homework Equations Ohm's Law Kirchhoff's Rules The Attempt at a Solution So I rearranged the circuit a little and got the total resistance to be three ohms and from...

Homework Statement Consider the circuit shown in the figure . Suppose the four resistors in this circuit have the values R1 = 12 \Omega, R2 = 6.4 \Omega, R3 = 7.0 \Omega, and R4 = 13 \Omega, and that the emf of the battery is \epsilon = 18V . A. Find the current through each resistor...

I'm working on 3.19 from Schaum's Outlines: Basic Circuit Analysis (not homework). The problem can be found at this...

When pulling up DDR2 signals with resistors, how to decide the power consumption of them, or I can just use 0402 resistors? And for the tracks connecting the resistors to the VTT (or the resistors to the signals), is there a impedance matching problem? Should them be of the same length?

Hey guys, I have a question about resistors in series. If resistors dissipate power which result in a voltage drop, then why is the voltage at the resistor the same as the supply voltage?

Homework Statement A 20 V emf is placed across 2 resistors in a series, a current of 2 A is present in each of the resistors. When the same emf is placed across the same 2 resistors in parallel, the current through the emf is 10 A. What is the magnitude of the greater of the 2 resistances...

in this circuit I've found out the function of every component except R4, R5 and C4,C7 and C8 ... can anybody please explain the purpose of R4, R5 and C4,C7 and C8 ? [PLAIN]http://www.2electronic.com/wp-content/uploads/2010/03/cellphone-detector.jpg also the Capacitor C5 (47pF) is connected...

Homework Statement Two resistors of X and Y are in parallel with one another and in series with a 200 Ω resistor and a battery whose emf is 1.5 volt and whose internal resistance is 0.5 Ω. The resistance of X is 100 Ω. When Y is disconnected from X, an additional resistance of 50 Ohms must...

Homework Statement Find the Thevenin equivalent seen by RL in the figure below: [PLAIN]http://img708.imageshack.us/img708/7023/thevenineqi.png Homework Equations RL = Load resistor The double-headed arrows indicate that RL is the loadThe Attempt at a Solution I know how to find the Thevenin...

Homework Statement What is the impedance of the circuit? Homework Equations Z=1/iwC ... Z = R ... etc.. The Attempt at a Solution What kind of equivalent circuit can i replace it with ? I tried only two resistors and two capacitors first .. then upgrade it by two resistors and one...

I have a project with two, separately wired high-power LEDs. LED #1 is a 1 watt LED rated at 3-4 Vdc at 350/700 mA LED #2 is a 3 watt LED rated at 2 Vdc at around 350/700 mA According to Resistor calculations, I get: LED #R1 = 4.7 Ohm, 2 Watt rating (for 700 mA) LED #R2 = 8.2 Ohm, 4...

hey can anybody please tell me how to solve this circuit?? :confused: I tried this sum out but I can't understand which points are symmetrical and have same potential..or how the current is distributed

Hi:) I was wondering if anyone could help me? I need to find: The resistor total, the current supplied by the battery, and the current through resistor R2. Given: R1: 3 R2: 7 R3: 12 R4: 10 emf: 6 volts I found the current through resistor R1 by taking 6v/3= 2 amps Thank you:)

I noticed that, for resistors in a parallel circuit, where R1 is < R2, the minimum value is (R1)/2, and the maximum approaches R1. I was trying to work out why, so for two resistors, the calculation is: R1.R2/(R1 + R2). I thought of partial derivatives but not sure where to go after that, and...

Homework Statement Two resistors when connected in series to a 110 V line use one-fourth the power that is used when they are connected in parallel. If one resistor is 2.0 kΩ, what is the resistance of the other? Homework Equations V=IR The Attempt at a Solution v=ir...