Battery Definition and 1000 Threads

Homework Statement Homework Equations Ohms Law R-total = R1 X R2/(R1+R2) Potential difference (V) = current (I) x resistance (R). The Attempt at a Solution [/B] a) Can complete on my own. b) Really no clue tbh, I would assume it revolves around ohms law but I'm not sure how it fits in...

Hello forum. How much current does a 36 volt battery draw under a full load? (Scratch the word battery in this first sentence and replace it with motor). I know I could find it under manufacturers web sites, but I cannot seem to figure it out quickly.

Hello, I have a question concerning electrochemical cells or batteries. It is said that when the battery is at open circuit, it has small charge separation on its electrodes thus having a potential difference equal to the emf of the battery. When the battery is connected to a circuit, the emf of...

Homework Statement (My english is not good) If I have a battery that is 4v why isn't U = 4 ? Homework EquationsThe Attempt at a Solution

Homework Statement How do I get the equivilent circuit in this scenario? The battery is not directly connected within the circuit. I know how to find the equivilent resistance in situations where the battery is "inside" the circuit but I am having a little trouble with this one. The voltage...

Hey, I have a project where my group needs to design a drill. I am wondering if anyone here knows how to calculate the torque we get from 3 AA-batteries on 3.6 V (10.6 V together). How does it work? It just needs to assemble furniture, so we don't need very much force on it. Do you know what...

I am doing my wrong project from school. Its basically a science fair but only for the students in the class. I came up with the idea to use piezoelectric plates to charge a capacitor that then charges one of those portable po charge a phone. I know I'm not the first one do this, but I do want...

For instance, at a point 1 meter from a 1 nC charge the voltage (potential difference) from the formula V = Kq/r, is given as 9 volts, 9 J/C. So what does it then mean to call a battery 9V, 9 J/C? Is this a battery capable of taking a 1 C charge from infinity and pushing to within 1m of a 1 nC...

First off, for my EE100 class I chose to replicate the industrial electrical blankets that are out there. With that being said, I do own one and can tell that there are some kind of conductive, insulated wires (copper?) that run throughout the blanket which generate the heat. And of course, the...

1. Homework Statement Homework Equations P=IV The Attempt at a Solution I used the terminal voltage of battery B, that is I minus the voltage across the internal resistance of battery B from the e.m.f. of battery B, then I multiply it with the current which is 2.5A (calculated earlier) ...

People keep asking about setting a car battery on a concrete floor somehow ruining the battery. Here is the final answer on the subject. I have the 1930s Popular Science with the original tip in it (but don't ask me which issue). The auto tip was: "Leaving a car battery on a concrete floor...

I am hoping to run the following motor using a 12v (car battery). This battery would run until a charge is needed Just curious on what's needed for an Inverter and how easily/cheap it could be accomplished.. Motor specsFHP-Motors 1~mot. 100w 115v 50/60 MHz I'm novice in...

Homework Statement A 2.9 V battery rated at 695.5 A(h) has been powering the same light bulb for 44.2 hours. The total resistance in the circuit has averaged out to be 5.3 Ohms. The light bulb has unexpectedly burned out, and was replaced with a new one. The total resistance in the circuit...

I need to model circuit given at (https://drive.google.com/file/d/0B8MN0_dZJLHZRllhV2Y0M0FnaVU/view?usp=sharing) so that we may known output for any state of switches. Given Information: Vector of State of Switches e.g. [s11 s12 s13 s21 s22 s23 s32]. I need to model a transformation matrix...

Homework Statement Show the change of potential of a system that contains a battery and two parallel connected resistors. Homework EquationsThe Attempt at a Solution I guess that there is no change in potential because they are in parallel. Or there is a potential drop trough resistors?

'The ends A and B of a potentiometer wire are connected a driving circuit consisting of a strong battery, a plug key and a rheostat. The driving circuit sends a constant current i through the wire AB.' Can anybody please explain me as clearly as possible what is meant by driving circuit and...

When I connected the positive terminal of the battery to one terminal of the bulb and the other terminal (of the bulb)to the ground the bulb did not glow, even when a potential difference exists?

I'd like to take several of these (or similar) usb device charging batteries (http://www.ianker.com/product/A1271011 ) and connect them into an array to create a minimum of 36V and channel that to power a speed controller for an electric vehicle. Is this possible? Would I be able to prototype...

I'm sorry if this isn't the right place for a shopping question, but I'm not sure where else to go for advice. I got a https://www.amazon.com/dp/B0094KM4VK/?tag=pfamazon01-20 on sale and the unit is great, but the batteries don't hold a charge very well, especially when using rechargeables - it...

so i want to make a ebike battery out of 18650 cells, I've done all the research about series and parallel and balance charging but what is still unknown to me is i know i want 36v coming out of the battery and i don't know how to find the amps that the battery is capable of putting out, is the...

How long can a 35 mAh battery charge a device that requires a 70 mA current? 30 minutes, right?

What effect (if any) would changing the surface area of electrodes in a lithium ion battery have? Would it allow for faster battery charging? Faster discharge rate? Thanks in advance

How to verify the Energy and Capacity delivered by the Lithium Ion battery? I have a Lithium ion batter with below configuration: Nominal Voltage 4.2 V Nominal capacity 2250 mAh I am calculating the energy and capacity every second for my experiments. I use below formula to calculate the...

Hi, I faced problem with the decrease the level of the batteries for UPS system and from time to time i filled the batteries but still the level decrease after one week... what is the problem and solution؟ best regards,

Something I have been meaning to ask when working on my car: Why is it that we have a 12 volt battery? Why not say 1.5 or 3 volts? Because if current is all that matters, then we could achieve higher current values to power one load (or multiple loads) with lower resistor values, no? Is it that...

Hi All, this question has been thrown around before but never fully answered so I'll put it very simply and cut out the ponderings: A 'gravity battery' could be created by using an energy source to slowly lift a large weight (using gearing or pulleys), then discharged by lowering the weight to...

I'm setting up an amplifier which is intended for use in a car, and I'm not using it in one. I'm trying to power it through a typical DC 250 volt wall outlet. What kind of transformer should I use? (I'm also trying to power a car stereo with it as well)

Batteries and rate of charge? I have an IPad. It 'seems' that when he battery if fully or mostly charged it lasts proportionately longer than when less charged. For instance, all things equal, the battery takes a shorter time to drain from 30% charged to 10% than it does from 90% to 70%...

I am just scraping the surface of electromagnetic induction, and I have some questions. First, let me illustrate what I know. I know that in a simple circuit with a battery and a switch, when the switch is turned on, a current flows which produces a magnetic field of strength in proportion to...

Hello everyone! I have a thesis to design a temperature stabilizing(controlling) system for solar cells.I need to use 12V Peltier battery and a simple pc fan.Any further help is appreciated.

Hello guys, I have been trying to calculate the maximum torque that can be applied to my driveline through regenerative braking, using the equations from this paper: https://smartech.gatech.edu/bitstream/handle/1853/47660/sambamurthy_aravind_201305_mast.pdf?sequence=1 I have been using the...

So for a DIY project I'm doing, I want to replace my iPhone battery (about 1810 mAh, 3.7V) with a NiMH battery (300 mAh, 1.2V) but I need help getting past some of the problems (and maybe more). First of all. I've read that iPhone batteries are non-removable, is this true? I've also read that I...

In a discharging battery, do current and voltage decrease over time? if so how does the battery accomplish the same amount of work over the course of its discharge with a lesser voltage or current?

Hello, I'm planning to light up a tile chess board with 64 LEDs (blue and white) set between the tile squares, and I was wondering if this Class 2 Battery charger output: 12VDC 900mA, would work to power 16 parallel sets of 4 LEDs + 1 ohm 1/8W resistor and a SPST toggle switch? The current...

Homework Statement 1. Find the power dissipated by 12 ohm resistor 2. What is the potential at points a,b,c,d? Homework Equations P=I^2R I=V/R The Attempt at a Solution For a) 3v-IR-6v-IR=0 9v=I(18) I=0.5 P=0.5^2 * 12 = 3 watts But not sure if the ground changes anything b) unsure if ground...

So I learned that outlets actually provide a lot more voltage than small electronics like phones need but that transformers are used for voltage optimization. Is the sole reason that this is the case is so that the battery generates less heat and doesn't affect the battery as much? Or is there...

To do this would you simply run the current from one battery through another in reverse? Would there be a significant loss in energy?

Will 12v electromagnet work with a 9v battery?

I have two batteries, both 1.5 volts one is 3800 mAh and 5800 mAh, does it mean that the 5800 mAh store more electrons?

I'm working on a very similar issue to the one shown below https://www.physicsforums.com/threads/linking-battery-packs-to-change-voltages-and-how-to-charge.514002/ I've found some batteries that should do the job. i need to keep them fairly small, and the length of charge doesn't matter too...

First off, I am a ME student, and I only know enough about electricity to get myself into trouble. I am looking to build a flashlight using a 100w LED chip, a step up constant-current transformer from 12V (or 24V) to 34V and either one or two 12V batteries (higher voltage to improve efficiency)...

good evening to all if two ideal cells with emf 6 volt and 3 volt are connected in parellel to supply current how the net emf can be decided

Hello, Stupid computer scientist student speaking here. I am looking to heat a few inch long glass tube with a OD of around 10mm and wall around 1.5mm wrapped in Nichrome wire to around 365F. Air will then be drawn through the tube to heat up herbs sitting about the glass tube. (vaporizer) I...

I am an electrical engineering student. I have been on summer break for a few weeks now and I had time to work on my project. This is not a school project but something I had wanted to complete for a while. I haven’t decided what I am going to do with it yet. I just built it for the fun of it...

If I connected 2 batteries together in series Positive-Negative-Positive-Negative, I've read many times the voltage (joules/coulomb) adds. I cannot understand what is going on to cause this at the ATOMIC level. Electrons in a battery are produced by a redox reaction and are attracted to the...

It is said that with dry hands, you can touch the poles of a car battery and it will not shock you. I understand this is because dry hands have a very high resistance. Now if you have wet hands, or even worse if you have needles stuck into your skin that are attached to the battery posts, this...

can you charge a 12v car battery with capacitor

Homework Statement The ammeter reads 5.0A. Find I1, I2, and ε Homework Equations ΔV=IR The Attempt at a Solution I've never dealt with ammeters before so I'm very confused. To start, I tried breaking this into loops, and then used Kirchhoff's Law. I started with the left side, since I...

Hi all, I am wondering if there is a need for impedance matching to charge a battery from the source? Thank you

I am designing a fishing pontoon boat at home. I am wanting to build into the pontoons a small water jet engine on both sides. Does not need to be jet ski type speeds. Just looking for an energy efficient motor that will exceed trolling motor speeds and still be small. I am more of a do it all...