Battery Definition and 1000 Threads

Hello, I have a small (24 Watt) guitar amp which I'd like to retrofit with a battery for outdoor playing. I actually study mathematics and do electronics mostly as an hobby, so I may miss some fundamental things (i.e. bare with me). Basically, I have two little problems which I'd like help...

Homework Statement I am trying to find terminal voltage of the batteries in the circuit shown. Homework Equations V = IR The Attempt at a Solution The solution manual says that it's the battery voltage, v, minus the voltage drawn from the resistance v = I * R. I understand this. I do not...

Homework Statement A team on The Apprentice have to come up with a new electrical device. They propose a hand cranked dynamo to charge a battery which initially uses the residual charge in the battery to power the electromagnet, instead of a permanent magnet (the idea being that this...

Homework Statement How long will it take the primary energy source to fully charge the battery pack from an uncharged state? (State your answer in hours, minutes and seconds, as appropriate.) t = 378 min. I = 100 mA Homework Equations Cb (battery capacity) = I x t The Attempt at...

Firstly i need to heat a wire to around 20 degrees or over using a low power battery which could last up to 24hours. what kind of wire is easiest to heat up? would AA battery's work? what would be a long lasting battery source? can it be done? please help me! thanks

charge lipo battery packs with a li-ion charger? hello. i am wondering if it is possible to charge lipo battery packs with a li-ion charger. for example what i eventually want to try is to replace the li-ion batteries of my laptop with lipo battery packs. so if i remove the original...

Sorry about the intrusion as I really don't belong here as I have absolutely no background in physics but I have a couple of questions regarding lead acid batteries that I have been unable to find answers to on the internet. First question - why does a battery spark/arc when the negative is...

if the electrical energy stored in the leaf's battery pack came from a standard power plant and was delivered by a utility company ( like United Illuminated or Connecticut light and power) it was generated, transmitted, and transformed to the DC electricity that a battery can store at no more...

Homework Statement Find the energy delivered by the 4.00 V battery in the circuit. R1=8.8 ohm, R2=2.5 ohm, V=15 volts, \Deltat=3.30 minutes http://www3.zippyshare.com/scaled/51639486/file.html I have already figured out the correct values and directions (see image) of the currents...

Homework Statement How long the camera can be operated in the 9.5 Watts recording mode using an initially fully charged battery. P = 9.5 W, V = 7.2 V, I = 1.3194 A Homework Equations (Cb) = I x t The Attempt at a Solution (Cb) = I x t = 1.3194 x 3600 = 4749,84 minutes...

Homework Statement Discharge time from battery if you have a pump drawing 4.4 amps with 12 volts dc and a light drawing 0.0545 amps with 110 volts (ac). Battery at max has specs: 12 volts, 144 watt hour, 12 amp hour. Homework Equations I'm not sure if you're able to add up the...

Hello, the question I am trying to solve is: A battery has a terminal voltage of 8V when it is connected to a 8 Ohm resistor, and a terminal voltage of 6V when it is connected to a 3 Ohm resistor. Calculate the values of the battery circuit components. I went about it like this: (using 'VS' to...

I've been trying to understand this but there are some points that lead me to confusion. The first is that a lot of people have been saying the the chemical reaction in the battery starts when you connect the two ends of the terminals to a load. I figured i guess the reaction won't take place...

Homework Statement Find the current in each branch of the circuit shown in the diagram (attached) if: V1 = 1V V2 = 4V R1 = 1\Omega R2 = 2\Omega R3 = 1\Omega Homework Equations V=I*R The Attempt at a Solution Okay, so I know that the voltage will be even across the parallel...

For my physics class this semester, we had a broad-ranged project to work on. Basically "anything related to physics" was the category. Initially I had wanted to build a percussion synthesizer circuit, but all I could manage to do was pick up a radio station 10 miles from my house, so I...

I've been doing a project recently that requires a UB1250ZH Universal Battery rated 12V and 5Ah. Although I understand the concept of Ah, I'm having a difficult time in figuring out what the ratings for standby and cyclic use mean. For an example, it says - Standby Use: 12.6-13.8V, the...

So I've been trying to work on this project that requires me to take a 12V AC to DC adapter (says 300mA on it) and supply power to a CPU fan (11.8V, 0.57A) and several LEDS (20mA forward current, 3.2V). My question is what does the 300mA exactly mean as I thought that there was no such thing as...

Hey everyone, I just went to Radio Shack and picked up a few parts to begin a book on Electrical Engineering/Electronics. I'm taking it slow and trying to understand the theory behind everything before I progress - something simple has got me confused though. I have two parts: Battery...

Homework Statement Okay, so there is a battery with in internal resistance r and voltage of (V). The battery is hooked up to an infinite number (N) of lightbulbs each with resistance R in parallel. The question asks me to find the current going through the first lightbulb...My problem is when...

Does adding more identical batteries in series allow more charge to be supplied or just affect the rate of charge being moved or both? Thanks.

Say for a example in a zinc carbon battery. The anode and cathode are placed in the same ammonium chloride solution as the electrolyte. The zinc outer shell is the anode and is separated from the cathodic Mn02/carbon paste by a thin paper. My question is on the electrolyte solution. If the...

Hello, This is a problem that is buzzing me around for quite sometime since I took fundamental physics course. Consider an electric circuit with one battery and one resistor. And ignore the internal resistance of the battery and the resistance of the wires. 1) Does battery supply...

Using TL084 and want to supply +/-5v for power. I heard there is a way to do it with 9v battery but I can't find any info. anybody have an idea on how its done? thanks

Hi, I need to power my HTC Desire cell phone for 4-5 hours on high load (running GPS navigation software on max screen brightness in an aircraft), so I'm looking into external battery packs. I want to avoid buying something too weak which will struggle to deliver enough power. The...

Triple battery Circuit? (Kirchoff help) Hey guys I really just don't know how to solve this... Can anyone help me? Like just give me some guidelines on how exactly kirchhoffs laws work and how i can use them on this problem? I need to find the values and directions of the currents in...

Homework Statement determine the terminal voltage in each battery. Emf1=18V r1=1 ohm EMF2=12V r2=2 ohm R=6.6 ohms also the batterys currents are opposing each other. Homework Equations Vab=emf-Ir The Attempt at a Solution i used kirchnoffs rule to find the current I ...

Hi, I have a maglite pen powered by 2 AA battery. I hadn't used it for years. I found out i was leaking chemical already at the rear, and I couldn't open the rear cap. I tried using wrench, pliers, hammers, nails which I insert to the hole at the rear cap and no matter how I twist and turn...

Homework Statement Why is the following situation impossible? A battery has an emf of E = 9.2V and an internal resistance of r = 1.2 ohms. A resistance R is connected across the battery and extracts from it a power of P = 21.2W. Homework Equations My book gives these equations throughout the...

Hi, I'm not sure if this is the right place to post this, but here goes. I'm trying to build a battery indicator circuit for 2 AA batteries (3V). So far what I've read online is that I'd need to use a Zener diode to get a fixed voltage drop, then connect it to a transistor, like the...

Here's my question. On a closed circuit, you have the electrons of the conductor being pushed-pulled around the circuit from the negative end of the battery to the positive end. So what happens to the electrons when they reach the positive end of the battery? In order for the electrons to...

I am trying to take two lights and usign a 9v battery switch between the LED's. My thought was if i could get a square wave to go from positive to negative, since the LED's are polarity sensative I could just put them in parallel with the positive of one and the negative of the other being fed...

Is it possible to use a 9v battery and run it through some circuit or system to get a squarewave output that has a positive and negative voltage. Ideally the two voltages would be the same but the negative of the other.

I need to power an op amp and my only power supply availible is a 9-v battery, the goal is for the device to be portable. I need to feed into the + and - sides of the op-amp. Would I connect the positive terminal to one end and the negative terminal to the other or is there some other set up I...

Hi friends, I am having a little difficulty understanding how amp hours being pulled from a battery are calculated, any help would be much appreciated! I have a 12v 125Ah deep cycle battery. Research has told me that for DC appliances you divide their wattage by 12V to give the amps, so...

Probably a very simple question, but I'm not sure of the answer... We have two batteries. Scenario 1: The positive terminals of both batteries are connected together and the negative terminals are connected together. Little to no current flows, correct? Scenario 2: The positive...

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...

Homework Statement The voItage U of a car battery decreaces as a function of the current I according to the formula U(I) = 12-0.3*I The power P of the starting motor is the product of the current I and voItage U , P(I) = U(I)* I. Homework Equations Find the maximum value of the power and...

We all know electrical energy is wasted when generators work to provide a voltage potential that goes used. Many different approaches to saving the energy have been proposed (and are being experimented on), such as storing the energy in a rotating drum, or in a superconducting coil. But what...

Let me begin by apologizing if this has been brought up before, but it has been on my mind recently, and I had to ask. Would it be possible to create a battery that can extract work from the casimir effect? I understand that the energy required to separate the plates is greater than the...

Hi there,can anyone please help me modify a battery level indicator that i picked out from the web.Its actually a small circuit that i need to modify without the charging circuit at the end.I need to change any resistance or capacitance if any.If you can help then would it be possible to show me...

Sumitomo Corp and Kyoto University have jointly come up with a new sodium-based molten salt battery which is claimed to have twice the energy density of Lithium-ion batteries, at only 10% the material cost. They hope to bring it to market in 2015...

What is the "driving force" to increasing the internal resistance of a battery Homework Statement A brand new battery almost have no resistance, but overtime when the internal resistance is great enough, the battery "dies". So my question is, what is causing the internal resistance to...

Pretty much every single electronic device in the world with an internal, rechargeable battery (MP3 player, phones, handheld games, etc) has some way of measuring how much energy is left in the battery. How do you measure the remaining energy in real time like that? How accurate are those...

Homework Statement Make a modification so that the battery is charged by the DC supply at a current of 10mA **See attached diagram** Homework Equations The Attempt at a Solution Well I know that I would put in a resistor in parallel with the diode. However, I don't know how...

What would happen if you just hook up a battery to itself, and a ground? I understand resistance is negligible in wires when there are other resistors, however, this doesn't seem to be the case when this occurs. But what happens? Battery drains extremely fast ?

Homework Statement When a 60 \Omega resistor and a 120 \Omega are connected in parallel across a battery there is a current of 700 mA flowing through the battery. When the 120 Ohms resistor is disconnected from the circuit the current through the battery drops to 500 mA. What is the emf and the...

When we connect a wire to a negative side of the battery, electrons flow from the negative terminal to the wire in order to make the electric potential same. That only happens for a short period.(the other side of the wire is loose) Having said that, what would happen if we connect just one...

The other thread was getting messy... Starting fresh again: We have two batteries. Let's say they are fully charged at 12Volts. We'll call them battery A and battery B. Is there a buildup of negative charge on the (-) pole of these batteries and a buildup of positive charge on the (+)...

can anyone provide me with a site explaning how to deal with battery in circuit ? for example when i use AA battery what max. current i can drive from it ?

hi friends i am working on project that is to generate electricity by using turbine which is integrated in the front portion of an electric car to charge the battery in turn which is used to propel the car. may i know how much efficient it is and what are the problems may occur to implement this...