Battery Definition and 1000 Threads

Now, to be honest, I can comfortably light it with TWO piece of wires and not ONE. So , was it a trick question? Technically, those are havard grads. Please weigh in.

So... I am looking to basically convert electric energy to thermal, then mechanical energy. I am wondering how practical it would be to use a rechargeable car battery (12V, and 40Ah) to boil water into steam for a steam engine. It does not matter how long it would take, simply if it is...

I was wondering if anyone could help me out here, Ive built a simple battery, using two separate types of metal (copper and zinc). Using a voltage meter I can clearly see a stable reading of 1.5 volts when connecting to the anode and cathode, however when testing this on a small moter which runs...

When I connect a AA rechargeable battery directly to a voltmeter, voltage increases slowly, regardless of the way I connect it. I can't figure out why.

Homework Statement There is a simple set up with a cylindrical solenoid that is connected to a battery. Suppose the solenoid has a total resistance of 0.2 ohms. If the battery were attached to a regular resistor of R=0.2 ohms instead of a solenoid, the current in the circuit would...

If I don't use my lithium polymer batteries for an extended period of time will that damage them? In that case how often should I charge them to prevent a such degradation? Thanks in advance

I have done a decent amount do research on this topic and can't find out about the "magic" that happens in the battery. I know that is is made of cathode which is the positive and anode for the negative with electrolytes in the middle. What I can't find is what anodes and cathodes are made...

Hey guys, I am building my own battery operated cell phone charger. I am pretty sure I built my circuit correctly because the outputs I am reading on my USB output port: pin 1 is 5V and on pin 4 is 0V... which are good readings (and tells me that my voltage regulator is functioning properly and...

Homework Statement Hello, long story short: I need to create a model of Li-Ion battery and I'm stuck on calculating the battery equivalent internal impedance. The thing is, I don't know the equation or even how to make one. However, I have a circuit drawing: Homework Equations Values in...

Homework Statement For a simple series LR circuit, find the energy delivered to the circuit by the battery. Homework Equations I = (V/R)*(1-e-Rt/L) P=IV E=∫Pdt The Attempt at a Solution Isn't ∫ Pdt = ∫ IVdt = ∫ (V2/R)*(1-e-Rt/L)dt = (V2/R)(t + (L/R)e-Rt/L) ? The book provides the answer, via...

A battery has an Emf 6 Volts. It is completely discharged. It is charged by maintaining a potential difference of 9 Volts across it. If the internal resistance of the discharged battery is 10 ohms, find the current through the battery, just after the connections are made. My textbook says that...

I am using a buck converter with a battery pack, for a usb charger. The issue is, is that the buck converter I have ( http://www.ebay.com/itm/DC-Converter-Step-Down-Buck-Module-7V-24V-to-5V-3A-5V-usb-output-power-adapt-/261030150117?hash=item3cc69bffe5:g:Q3UAAMXQTT9R0Qos ) has a led on it, which...

Homework Statement There is a battery producing emf V and the current around the circuit is I. The battery has an internal resistance of R. What is the power transformed by the battery Homework Equations P = VI P= I2R The Attempt at a Solution Maybe P=VI+I2R because there is some electrical...

Hello everyone, How much of a safety hazard is it to store a car battery inside a classroom/lab? It's a new battery and it is plugged into a charger all the time. I use is only couple of times per year for a demonstration. Thanks! -Gamma

Homework Statement Will current flow in an ideal circuit given that there is only an ideal battery in the circuit? Homework Equations V=IR The Attempt at a Solution Since there is no resistance through out the circuit no potential is dropped so no current flows

hi all, i am embarking on a new project, building a outdoor rolling credenza that has TV (with air operated TV lift), cd player, small receiver, 100% wireless (power and wifi, etc). my design calls for a battery pack that can deliver approx 5x106 joules, this leaves me in the ballpark of...

Homework Statement Find the current through and power dissipated by each resistor Homework Equations V=I/R ΣIin=∑Iout The Attempt at a Solution Did I set up the loop laws correctly and where do I go from here?

Homework Statement When a certain 9.0V battery is connected to a voltmeter, the voltmeter reads 8.00V (assume that the voltmeter has an internal resistance of 10MΩ. We may conclude that (A) only 1/9 of the battery's fuel has been used, and so the battery has plenty of life left in it. (B) the...

Homework Statement A real battery can be modeled as an ideal voltage source in series with a resistor. A voltmeter with input resistance of ##1000\Omega## measures the voltage of a 1.5V worn out battery as 0.9V. What is the internal resistance of the battery. Homework Equations ##V=IR## The...

I'm in charge of designing a battery bank (using 18650 batteries) that will produce large amounts of heat for a short period of time. The battery bank will be in a near vacuum (~800 Pa), so convective heat transfer will not be effective. Since the operation time is only ~80 seconds, my thought...

I live in an rv. My power comes from solar and ocassional boost from my generator. I have 3600wh in battery power. But i know its really bad for my batteries to draw lot of power fast. So i would like to create a capacitor bank that would stay charged. Ive done some calculations but not...

Hi all, For some reason I'm really struggling to understand how batteries store energy and how this relates to electric potential. Can I just think of a battery as two separate plates one accumulating positive charges the other negative. The positive and negative charges are attracted but they...

I conducted an experiment to find out the emf of a battery, the result turned out to be 1.35 volts , however on the battery, it says the battery is 1.5 voltage. Does it mean that my method is wrong or less accurate. But I used three different methods:1) measuring the terminal voltage across...

Hello PF, I am a middle school teacher in Humboldt county, CA and teach physical science to eighth graders. We are beginning our electricity and magnetism unit and have students have experimented with making a light bulb illuminate using a battery and copper wire. My question is, if we make a...

Homework Statement [/B] Three resistors are connected to a real battery. The open circuit voltage of the battery is 4.5 Volts. The voltage across the 5 Ohm resistor is 2.5 Volts. A) What is the voltage across battery terminals? B) What is the internal resistance of the battery? Here's a...

Homework Statement The problem includes a graph. All I have is a current to external resistance graph, with 20 A coming at 10R of external resistance. I am to find the EMF and internal resistance of the battery. Here is the problem and my two attempts. http://1drv.ms/1LKbu5H Homework...

So I want to charge a battery from a pedal-powered dynamo, and use that to power my PC, my screen, and pretty much everything else in my home office. This whole thing is a little project to improve my own health while I'm working; I'm not here expecting to make major miracle savings on the...

Homework Statement Three resistors are connected in series to a battery. The resistances are R1 = 15 Ω ,R2 = 25 Ω , and R3 = 30 Ω and the current through the 15-Ω, resistor is 2.7 A . What is the potential difference across the battery terminals if the battery is ideal? What is the potential...

Hi, I am working on a piezoelectric energy harvesting project. i was able to use my piezoelectric to charge up my AA NI MH battery 1300mAH from 0.93V to 1.201V. However, once i removed the battery from the battery holder, the cell voltage starts to drop without being connected to any load...

Hello there everybody In my research group we've been working on PV cells and exploring non-conventional techniques to try and raise the efficiency of some of the lesser explored materials that have PV potential. Well, last week while testing one of our cells in a solar simulator, we noticed...

Hi Experts, I'm preparing piezo electric generator project, but when I'm searching for piezo disc for my project, i came across different sizes of piezo electric disc, but i didn't found any datasheet, My question is what's the output voltage/power difference between different diameter...

Homework Statement A constant current of 3A for 4 hours is required to charge an automotive battery. If the terminal voltage is 10 + 1/2 t V, where t is in hours, (a) how much charge is transported as a result of the charging? (b) how much energy is expended? (c) how much does the charging...

Hi guys I'm not sure if this is the best place to post this but I couldn't find anywhere else. Would it be possible to program a cell phone charger to detect when a phone is at 20% and then it will start charging? But it won't start charging before 20%. Then it will charge it up to 99% and then...

Hi, I recently bought a new battery for my phone, and before installing it, checked it's voltage, to be Zero. I understand that there may be protection circuits in the battery, but I assume it should still show a voltage. As it's a Li-on battery the voltage should be between 3.5 and 4.2v. The...

Have been trying to better understand how batteries work. Forgive me if the question's naive. A half-reaction on one of the electrodes in a battery produces free electrons (for example) and consumes anions (or produces cations). I understand why, if there's an external wire for electrons to...

Homework Statement When the resistor is R1, in the circle there is the intensity I1 and when the resistor is R2, the intensity becomes I2.Find emf and the inner resistance.[/B] Homework Equations I=emf/R+r The Attempt at a Solution I1=efm/R1+r I2=efm/R2+r efm is equal I1*(R1+r)=I2(R2+r)...

Homework Statement A battery is connected with a resistor R1=4 om and then it is replaced with the resistance 9 om. In both cases the heat released in the same time is the same. Find the inner resistor of the battery. Homework Equations Q=UIt (U-tension; I-intensity, t-time) I=e.m.f/R+r The...

Homework Statement A 5V battery rated at 1800mAh has a soucre resistance of 10 Ohms. What is the maximum power that can be extracted from the battery? Homework EquationsThe Attempt at a Solution I understand that had the battery not had any source resistance then the power out would have been...

I'm going to weld nickel plates/tabs to 18650 cells. Each two batteries will be welded together with a nickel plate. In the center of the nickel plate will be a copper wire to take the 20 amp current flowing from the two cells at 10 amps per cell. Since I have .2 mm thick nickel plates, to get...

Can a supercapacitor be a power supply?

Hello, according to the lead acid battery standard equations The overall chemical reaction is: At the negative terminal the charge and discharge reactions are: At the positive terminal the charge and discharge reactions are: My Q? If we empty all liquid from old battery and add H2O...

On average it takes about 30 seconds for hot water to reach the shower, so for 30 secs water is being wasted. I know running water for 30 seconds doesn't seem that bad but there are a lot of water shortages and droughts going on all around the world. I know its possible to heat water with 9v...

So I have a good car battery at around 12 V and a bad car battery discharged to 6 V. I hook up the batteries (sitting in the cars) with jumper cables. Now, before I turn the ignition switch on the dead battery car, there is effectively a circuit between the the good battery and the bad...

How car alternator charge battery..?? Both equipment are connected with same cable so why battery power does not reached at alternator?? If you guys have any animation it would be helpful..

How battery cut off switch works?? How to apply Battery cut off switch on a vehicle..?? I want to make some electric functions to be operated if the battery is cut off. For this what should I do..??

Hello, Sorry for a newbie Q. If I have a 340ah Lithium LifeP04 12V battery in my camping trailer... its BMS set to 5% (for a drainage of 95% = 323 usable amp hours)... it is hooked to an inverter claiming to have 88% efficiency... how many AC watts (@ 120V) can I expect in theory, or...

No it is not a homework problem I made it myself in order to clearly explain what I am trying to ask.The question could be invalid and silly therefore .If there is a 9V battery What is the potential of it's positive and negative terminals respectively? If positive terminal's potential is 3V and...

Homework Statement An electron moves from the positive to the negative terminal of a battery (9V). How much potential energy did it gain or lose? Homework EquationsThe Attempt at a Solution Solving for the amount is basic. That's just qV = 14.4 * 10^-19 J I'm not sure whether it will gain the...

I have a question that how ignition switch works. Is it is directly connected to battery..? or Alternator..?? Further If I apply a Battery Cut-Off Switch, will ignition works when Battery Cut-Off Switch is off..??

Hello, Inside an ideal battery, the chemical reaction is reversible (at equilibrium), thus the oxydation-reduction reaction Zn + Cu2+ = Zn2+ + Cu is happening in both ways at the same rate right? Now, for a real battery, there's resistivity inside it due to many factors, thus the chemical...