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 ovais Feb1-09 03:02 AM

Will a batteries get discharged if the positive one is connected to the negative

Hi,yestrday i was told when a wire is connected between two bodies being charged oppositely 'and equally in magnitude' then a sudden discharge take place making the bodies uncharged.So what about the charged terminals of a batter 'if you consider they are realy charged.when the +ve of one battery is connected to -ve of another battery.'Will the battery's terminal get discharged with a sudden discharge so that no continous flow of charge .Thanks see Are the terminals of a well-charged battery neutral?

 CompuChip Feb1-09 05:59 AM

Re: Will batteries' terminal get discharged if the positive one is connected to

Basically a battery is a two-compartment cylinder with lots of positive charge in one compartment and lots of negative charge in the other one, which are insulated from each other. When you connect a resistor (such as a light bulb or a resistor component) to the battery, then charge will start flowing through it to try and lift the charge difference in the battery (depositing energy in the resistor as it goes through, thereby lighting your light bulb).

Now suppose that we directly connect the terminals by a low-resistance wire... what do you think will happen? How is it called?

 ovais Feb6-09 05:06 AM

Re: Will batteries' terminal get discharged if the positive one is connected to

Thanks Chip for your reply to my question,actually i did not represent the question in the way i should.What that i want to know is that 'will the batteries get discharge when positive terminal of battery# 1 is connected to negative terminal of ANOTHER BATTERY #2 through a conducting wire' Will there be any flow of charge from one battery to another,when +ve terminal having DEFICIANCY of electrons, is connected to -ve terminal having EXCESS of electrons.Thanks in advance.

 ovais Feb6-09 05:18 AM

Re: Will batteries' terminal get discharged if the positive one is connected to

Do the EXCESS electrons of negative terminal of battery # 1 have no atteraction for the positive terminal of battery # 2 having DEFICIANCY of electrons.If yes what force CANCILS the attraction.what force ristricts the EXCESS electrons avialable on the negative terminal of battery to go to the positive terminal of battery # 2 which has DEFICIANCY of electrons.I read in my texts that when a +vly charged body is connected to a -vly charged body through wire then electron move from -vly charged body to

 ovais Feb6-09 05:23 AM

Re: Will batteries' terminal get discharged if the positive one is connected to

+vly charged body untill the EXCESS charge either cancil or equal in both bodies.But this does not seem to happen if the charged bodies were terminals of two batteries. WHY??? Please explain

 p.tryon Feb10-09 11:35 PM

Re: Will batteries' terminal get discharged if the positive one is connected to

In answer to your first question:

Electrochemical cells are complicated! If you have some chemistry background I recommend reading about galvanic cells to try and understand them better.

Compuchip claimed "Basically a battery is a two-compartment cylinder with lots of positive charge in one compartment and lots of negative charge in the other one, which are insulated from each other."

Strictly this is not true. If the separate compartments were electrically insulated from each other- when they were connected there would only be a transient (short lived) flow of current until the electric charge of each terminal were equal (you were correct on this point). However, the salt brige (between the compartments) allows negative ions to flow from the solution of the positive compartment to the solution of the negative compartment. So charge and therefore current does flow through a battery in the direction that current flows round the circuit. However, that charge is transfered via the migration of ions rather than movement of electrons.

 ovais Feb26-09 10:16 AM

Re: Will batteries' terminal get discharged if the positive one is connected to

Thanks p.tryon.i am sorry for being so late.Actualy i was new to the forum those days.Well, within this period i have learn quit much about batteries.I have learnt that batteries give enery by an
electrochemical reaction.The electrochemical reaction 'between electrode and electrolyte' causes generation of opposite charges at the two electrode.The generation of charges or more correctly the electrochemical reaction is caused by a chemical tendency called chemical potential.its vale depends on the nature of

 ovais Feb26-09 10:17 AM

Re: Will batteries' terminal get discharged if the positive one is connected to

Thanks p.tryon.i am sorry for being so late.Actualy i was new to the forum those days.Well, within this period i have learn quit much about batteries.I have learnt that batteries give energy by an
electrochemical reaction.The electrochemical reaction 'between electrode and electrolyte' causes generation of opposite charges at the two electrode.The generation of charges or more correctly the electrochemical reaction is caused by a chemical tendency called chemical potential.its vale depends on the nature of

 p.tryon Feb26-09 06:23 PM

Re: Will batteries' terminal get discharged if the positive one is connected to

Hello!
No problem. I have been reading up too because I have been teaching circuits in physics and it is one of those areas that is not covered well in many text books. I am glad you have found the answers you were looking for :smile:

 Delphi51 Feb26-09 07:22 PM

Re: Will batteries' terminal get discharged if the positive one is connected to

No current will flow when battery 1 is connected to battery 2 by one wire. A complete circuit with wire returning to the other side of the battery is necessary before current can flow.

There is no actual charge in the battery - you could bring a very sensitive electroscope as close as you like to any part and it will give no indication of charge.

 p.tryon Feb26-09 10:11 PM

Re: Will batteries' terminal get discharged if the positive one is connected to

Don't metal atoms leave the negative electrode (ionizing) leaving their electrons on the negative terminal when the battery is not connected? Surely there would be a net negative charge even if its not detectible??

 Delphi51 Feb26-09 10:27 PM

Re: Will batteries' terminal get discharged if the positive one is connected to

It has been nagging me, too. The standard answer doesn't quite satisfy.
Yes, there must be some charge because there is a potential difference between the terminals causing an electric field - and only charge can create an electric field.

Using the two formulas for electric field, we could very roughly say
E = kq/d = V/d or q = V/k
For a 12 Volt battery this is something like 12/10^10 = 10^-9 Coulomb.

And there would be a tiny flow of current when one wire connects a battery to something.

 p.tryon Feb27-09 12:46 AM

Re: Will batteries' terminal get discharged if the positive one is connected to

I find electrochemical cells really confusing :confused: Is that 12V/k? What does the k term mean? Was that the value 10^10?

 ovais Feb28-09 09:50 PM

Re: Will batteries' terminal get discharged if the positive one is connected to

O' my network is not proper,i will soon subscribe from a batter company. Though i have studied about batteries 'mapes helped me a lot' but one or probably more things is still not understood.when +ve terminal of battery#1 is connected to negative terminal of battery#2 a momentary current flows from battery#1 to battery#2 and after the moment current stops. since the connected terminals must now be at same potential.actually in battery charge on both side in not stored in major amount but charge

 ovais Feb28-09 10:03 PM

Re: Will batteries' terminal get discharged if the positive one is connected to

Formation is a result of chemical reaction.At one time a small amount of reactant react to form products and a small charge at the terminals the reaction doesn't go continously because of electrostatic potential. what that happens is that when the electrodes are dipped in electroylte at one electrode the chemical potential tends to charge that electrode with +ve charge and the chemical potential at other electrode tends to charge that electrode with -ve charge. but as the separation proceeds, an

 ovais Feb28-09 10:13 PM

Re: Will batteries' terminal get discharged if the positive one is connected to

an electrostatic potential 'due to separated charge' begins to grow and it opposes further separation of charge i.e. opposes chemical potential's effect.the chemical potential tends to separate charges while the electrostatic potential tends to re-unite the separated charges.but both are now 'after the electrostatic potential achive a suffeciant value' unable to show their effect.because

 ovais Feb28-09 10:23 PM

Re: Will batteries' terminal get discharged if the positive one is connected to

Chemical potential is unable to show its effect on charged electrodes how much charge it could provide it provided to the terminal when terminal was neutral.and electrostatic potential fails to achieve its purpose because electron can not cross or pass through electrolyte.thus in not normal a battery is in a state that both chemical and electrochemical potential being equal and opposite.and battery is used to draw curren by putting a load in between its terminal some electrons from negative terminals begins

 ovais Feb28-09 10:44 PM

Re: Will batteries' terminal get discharged if the positive one is connected to

To move from negative termimal to positive termimal through connecting wire.this causes electrostatic potential'which was due to separated charge' to be decreased.now the chemical potential dominates.hence the electrodesnow achieve the same charge. thus charge on electrodes does not remain large amount but produces and end as the battery operates to deliver energy to the load.Now imagine the condition when +ve terminal of battery#1 is connected to -ve terminal of battery#2.since the terminals must have

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