Voltage drop Definition and 201 Threads

Hi Guys, I have a model gas turbine that is driven by an ecu ... the ecu starter output is 12.6volts but the starter motor is rated to 6volts. The ECU can easily supply 20amps although the starter motor is rated to 5amps max efficiency. I need to drop the voltage from 12.6volts to...

Dear Experts I just connect a diode to a battery rated at 4.2 volts. The diode takes about 0.8volts ( i thought should be 0.7v but measurement says 0.8v) and the battery is currently at 3.12v. The supply voltage is 5v dc. After some time, if the battery reaches 4.2v, would current...

Electrical question: I live in Mexico ( retired ex-pat ) and my electrical supply ( 240 volt single phase ) comes through a transformer that is almost 1 km away from my house. The supply lines are 2-0 aluminum. Because of the distance and from usage by others on the line, the voltage is...

Hi i built a circuit for a project and I am having some trouble working out important factors of the circuit. My circuit is powered by a 12V power supply, its wired in series, it contains 85 LED's that are connected with a 1kΩ resistor across 3 off the LED's. This is then connected to a PIR...

I have just wired up a LED circuit in series of 3 with a resistor of 1000 ohms 1.6W on each 3. Its being supplied via a 12 V battery. The circuit is wired up to a PIR which when detects movement the LED's will light up. I need some help working out how much current will be running throughout...

I want the LED to be off when there is a certain input voltage let's say 5v (the exact value doesn't matter), but when that voltage drops I want the LED to turn on. I would also like the LED to remain on even when the voltage goes back up to 5v. I was thinking of using some sort of logic gate...

A 3v battery is connected to a capacitor and 2 light bulbs all in parallel set up 1. Where is the total voltage drop at t = 0 2. Where is the total voltage drop at t = infinity 3. Which light bulb is brighter? From my understanding, since this is in parallel set up at t = 0 the voltage...

Hello guys, so I had a homework and I couldn't understand the point of my teacher. The question goes like this: http://desmond.imageshack.us/Himg3/scaled.php?server=3&filename=21976607.jpg&res=medium So the question is, "Calculate the voltage drop over the TRAIN when it is at the...

How I am currently imagining it: In a simple circuit with just a battery and resistor the voltage of the battery sets the electrons off through the circuit at some speed and that speed is proportional to the voltage. The electrons then encounter the resistor. From these forums my...

If specs on a 300Hp electric motor; 480 Volts 3 Phase 60Hz The full load Amps of the motor is 361A, which I found in the NEC table. My distance is 700ft to a control center and I can't seem to figure out what copper conductor size to use. In order to find the Voltage drop I have to know...

Homework Statement Voltmeter has a internal resistance of 10M ohms and the resistor has a resistance of 100,000ohm. The current through the resistor is 1mA. a)What is the voltage drop across the voltmeter? b)What is the current through the voltmeter? Homework Equations V=IR is all you...

Homework Statement Find the voltage drop across a resistor and capacitor in parallel. I am trying to understand how to deal with this using complex numbers. I may have a completely wrong notion of complex impedance. I thought I could treat the complex impedance like resistance, then take the...

Homework Statement So I have a problem that I am working on that requires me to find the voltage drop across a 1000 mA current source, and two 2000Ω resistors that are in parallel. I've added a picture of a circuit diagram for this below. Homework Equations V = I * R The Attempt at a...

Hey everyone, I could do with a hand checking my understanding of calculating the current loss in cables just to make sure I am doing it right. First up, is power loss. From my understanding of ohms law and P=VI it is possible to calculate the power loss in cables by using the formula power...

Relevant equations: V = I*R ε = I*(R+r) Then, V = {ε/(R+r)}*r V = potential difference, ε = electromotive force, R = resistance of external load resistor, r = internal resistance of the battery. So say the external load resistor's resistance is a constant for two batteries of the...

I'm currently studying electric circuits and can't find the answer to my question anywhere so far. I realize current is the flow of positive charge even though positive charges stay put in reality and that this is an old historic concept that is still around today because Benjamin Franklin...

Hello, I am a computer engineer that specialized more in software but I am trying to remember the electronics part. In the book I read there is an exercise where a diode (forward-biased) is connected in parallel with a resistor and then both of them are connected in series with another...

Voltage Drop Between Sender & Receiver ...( help needed ASAP , Thanks in advance ) hello every body I'm EE student and I'm new member here ... in a deep need for your help & knowledge I'm doing some reading about the power transmitted from the sender to the receiver end , As we all know...

Say the voltage drop of a diode is .7 volts. Once the voltage drop has been reached, and it begins conducting electricity, can the voltage be backed off to around .3 volts and it will continue to conduct electricity? Or does the amount of electricity need to be a constant .7+ volts?

This is not a homework question. Why is the voltage drop on an inductor opposite the electron flow? "When the current through an inductor is increased, it drops a voltage opposing the direction of electron flow, acting as a power load. In this condition the inductor is said to be charging...

So the voltage drops across closed circuits I get that is P = V^2/R to get the power and then you will use P=I^2/R to get the current running through the circuit and in the case the current flowing through the closed circuit is equal in every resistor and so is the voltage drop. The part that I...

I have a circuit with 3 meshes for which I have to find the mesh currents, and I have. However, I just thought that there might be a voltage drop over the dependent current source in the circuit, which would change the mesh current equations. The CCCS is shared by two meshes. When I did the...

i have problem to conceptualize this old galvanometer readings for voltage drop. i plot a diagram of circuit of interest for bether explanation of what's bothering me. so, in DC circuit with some resistor in series, electric current is constant and is of some known value. and if i want to use...

Hi. I'm hoping someone can help me out with a pretty simple physics question. My electrical circuit skills are pretty rusty, so please bear with me. I'm using a 19V DC laptop adapter to power a 12V DC pump motor. The pump is rated for 3.5A. I have an on/off switch between the power supply...

When we take down voltmeter readings from the terminals of a Rectifier (rated 12V), we get the voltmeter reading as 4.5V. Does that mean the rest of the voltage is lost in the form of voltage drop? or is it because of the current drawn by the load? I would be glad if someone could please post...

Resistor Capacitance Circuits.Say there is a resistor before a capacitor connected in a wired circuit; and there is a battery as the emf source (10V for example). How can the capacitor be charged to approx. the voltage of the battery if the voltage drop across the resistor = the voltage of...

I have written this problem myself to present to my professor. He teaches HVAC and Electrical for the department of Construction Management. Some of the problems and solutions we do in class are inconsistent with the material I was taught in physics. He really appreciates my criticism and I...

My textbook tells me that the voltage in an electric circuit only drops across a resistor. I don't quite understand this; doesn't this suggest that the electrons in the current are moving at a constant velocity? I would think that, since they are moving under the influence of an electrostatic...

Why can't I add the voltage drop?? Homework Statement What are the expected readings of the ammeter and voltmeter for the circuit in the figure below? (R = 6.00Ω , ΔV = 6.00 V.) The Attempt at a Solution I already solve for the ammeter, but the voltmeter is confusing me...

Homework Statement Measure the Voltage drop and current in all element of the circuit, given the figure which has the following Resistance and its Ideal emfs; R1=20ohms, R2=70ohms, R3=55ohms, R4=45ohms, R5=30ohms, R6=20ohms, R7=70ohms, E1=15v, E2=5v, E3=5v. Homework Equations...

Homework Statement Three batteries and four resistors are connected in a loop as shown (see attachment). What is the voltage drop across the top left resistor? Homework Equations V = IR The Attempt at a Solution This is part 3 of the 3 questions for this problem. On the other...

I am a little unsure about why the ideal diode can't have positive voltage drop... Looking back at my notes, it just simply says that "It's not a feasible solution" and that only when voltage drop is zero or negative can there be a solution.

So this is the question... In the direct circuit diagram below (please see the attached file), Resistors 1 and 3 have fixed resistances (R1 and R3, respectively), which are known. Resistor 2 is a variable (or adjustable) resistor, and the resistance of Resistor 4 is unknown. Show that if...

I have a source of 800 Kilo Ohms and I want to power an LED with that source. Which I would presume the LED would have a resistance of 9.5 to 10 Ohms if I'm correct. When I connect the LED to the source the voltage drops from 12 volts DC to around 1 volts DC. If my thinking is correct the reason...

Hi, ok so everytime I think that I have understood the concept of Energy transmission, losses and voltage drop, I get even more confused about things. I have searched several threads on this forum and the physics forum but failed to find anything that directly answers my query. So I...

so I'm working on a physics lab report, and I've derived the following formula V=-N∫dB/dt(dot)dA then I used the chain rule to turn it into V=-N∫dx/dt * dB/dx(dot)dA my question is, can I pull the dx/dt out of integral? I was doing the experiment, and measured the voltage drop, and...

I am trying to help a student understand the concept of voltage drop but I'm not sure I fully grasp the concept myself. From Conceptual Physics 9th edition "The total voltage impressed across a series circuit divides among the individual electrical devices in the circuit so that the sum of...

greetings what is the difference between voltage and voltage drop? in text i read as follows and i could not get When the voltage on the base is very close to 0.6v, the transistor is just at the point where it is turned ON and the voltage on the collector will be say 8v for a 9v supply...

I don't understand the Vce voltage drop of a BJT. If I try to think of the BJT as 2 diodes - Base emitter diode and base collector diode. Vce is the voltage across the cathode of the base-collector diode and cathode of Base-emitter diode. How can it be 0.2V(when the BJT is saturated). I don't...

Suppose I have finite wire of known resistivity. I know voltage is 0 volts at x=-1 and x=1, and 1 volt at x=0. How do I find voltage at intermediate points?

Homework Statement Suppose you want to run some apparatus that is 75m from an electric outlet. Each of the wires connecting your apparatus to the 100V source has a resistance per unit length of 0.0055 ohms/m. If your apparatus draws 2.5 Amps, what will be the voltage drop across the connecting...

Preface: Newbie here. Sorry if this has been asked before - I did have search but couldn't quite find what I was after. Also, I'm not putting this into the electrical engineering section because I don't want what will inevitably be an electrical engineer's answer =) Here goes: Voltage across...

Hi, I am hoping you can help me understand this concept. I've always known that generators operating a leading power factor lowers voltage drop and a lagging power factor increases voltage rise (as seen here...

so the reason why alternating current is used to deliver energy to households is because for a given wire, the voltage drop is always less with ac rather than dc right? but when i calculate the voltage drop it coumes out to be the same! v=IR R=P(length of wire)/(cross section area of wire) i...

Homework Statement I want to know that if there is a voltage drop across a resistor, why is it that voltage increases as resistance increases (Ohm's law)? Homework Equations None. The Attempt at a Solution N/A

Homework Statement The circuit has a battery Voltage of 30V, a resistor of R1(8ohms), R2 (2Ohms) and R3 (4ohms) in series. Calculate the voltage drop over R1 Homework Equations Please give me the proper equation of this? The one I've got says you take 30-8I-2I-4I=0 Wich gives you...

Homework Statement heres a picture of the problem. Please don't give me the answer just tell me what are the steps to complete it. thanks. http://i307.photobucket.com/albums/nn296/alan1592/download-1.jpg Homework Equations V=IR The Attempt at a Solution 1/6+1/3=2 Ohms

On a test in college I was asked to find the current flowing through a resistor and lightbulb on a simple circuit with a battery, resistor and lightbulb. I was told the resistance of the resistor and was given a voltmeter so I measured the voltage across each of the components but when it came...

My textbook says that electrons in a wire begin with electric potential energy- they are then accelerated by the electric field and their potential is converted to kinetic. Once inside a resistor, they collide with molecules and their kinetic energy is converted to thermal energy. However, it...

Homework Statement Homework Equations V=IR (Ohm's Law) The Attempt at a Solution Now I'm able to get V=0 for when R=0 but I'm not sure as to how to solve for I when R=0. Can I ignore the 10 Ohm resistor as it's a short circuit as R=0.