elctricity

Discussion in 'QnA (read only)' started by william, Sep 13, 2006.

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  1. william

    william New Member

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    Last edited: Sep 14, 2006
  2. blackpearl

    blackpearl The Devil

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    Where did you find this strange ckt diagram?

    Both the batteries will drain out and no current will pass through the resistor. If you forget the resistor, then basically the circuit consist of 2 batteries connected end to end. That will drain out the batteries as no resistor is in the path. Now when you connect the resistor in parallel, no current will pass thru it as the batteries are already shorted (current always takes the path having the lowest resistance.)
     
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    william

    william New Member

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    thanks blackpearl for your reply but i still expect some more answers as this is the controversial topic going on between my friends.
    Now i want to ask one thing if you treat the resistor as a wire?
    another thing if emf of one battery is greater than other than what?
     
  4. blackpearl

    blackpearl The Devil

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    If you change the resistor with a wire i.e. a conductor, then both the batteries will again discharge but this time via the wire as now the wire becomes the path of least resistance. It does not matter if the batteries have different emf. When you add 2 batteries (of different or same emf) in series (first case), then the resultant emf will be the sum of 2 emfs. In the second case (resistor replaced by wire), you have 2 batteries that are both shorted with the same wire. So both will discharge individually through the wire and the total current passing thru the wire will be the sum of currents due to both the batteries.

    Read about superposition theorem.

    http://www.allaboutcircuits.com/vol_1/chpt_10/6.html
    http://hyperphysics.phy-astr.gsu.edu/hbase/electric/suppos.html
     
  5. Rollercoaster

    Rollercoaster -The BlacKCoaT Operative-

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    wanna let me in on the hidden agenda or somethin..

    what exactely is being attempted here...

    if u want to knwo if current passes thru the resister then yes it will but in very low qualities..

    both battries will just behave like a resister(low if in series and high in ||el) to each other.. the resistence being equal to the 'inter resistance' of the opposit battry....

    i still dont get what is it that u want to know?
     
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    william

    william New Member

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    @ rollercoster
    i want to know what willhappen in the case of the circuit diagram i have provided, as a link. check it and then tell me , please sate the reason for it.



    This is for to other members that one reply i have recieved from my friend is that nothing will happen in circiut as resultant emf will be equal to 0.
     
  7. Naveed

    Naveed New Member

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    r u electrical engineer?
     
  8. blackpearl

    blackpearl The Devil

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    Batteries don't explode on short ckting. The wires will heat up due to heavy current flow and might burn or melt, whatever. Nothing more than that.
     
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    william

    william New Member

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    Friends i will post more queries and questions about this tommorow as i am going to ask this from any teacher by that time keep on thinking of new possiblities.

    and by the way naveed i am not electrical engineer rather i want to become computer software engineer ( application and operating system programmer). if you can tell me anything i need to know that will help in my aim then i wil be thankful to you.
     
  10. aditya.shevade

    aditya.shevade Console Junkie

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    Nothing will happen if the batteries are of low emf as 1.5V (normal dry cell) exept that they will heat a lot. If they are of higher emf then they will heat even more and may result in melting of the wire. Why do you want this anyways?
     
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    william

    william New Member

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    i wnat to know because my friends were not ready to accept what i was saying that i wanted your opinion and now everything is fine.
     
  12. shaunak

    shaunak Tux Fan

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    The resistor load will be divided on both the batteries. Little heat may be caused depending on the resistance.Nice way to waste 2 perfectly good battries.
     
  13. romeo_8693

    romeo_8693 "The RaCaLaNGeL"©

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    if the two batt are of diff emf's then the voltage across the load res will be the diference of the two voltages...since the currents are flowing in opp direction so they will cancel each other hence only the differential current will flow....if the two sources are equal then potencial across load will be nil since both currents will cancel each other completely....
     
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    william

    william New Member

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    What i mean to say is that in this case battery will blow up as soon as you will connect the circuit,instantly
     
  15. Rollercoaster

    Rollercoaster -The BlacKCoaT Operative-

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    this is dumb. there is no question to be answered...

    and NO the batterys wont blow "instantly" and NO there will be no heat at the resister as the current will be too low. in case some people have forgotten electricity has the basic property of following the shortest path(less resistance=less work).. for eg lightening in sky.

    dude bill william gates... post an accurate question then maybe some physics can be exchanged :)
     
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    william

    william New Member

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    but dear rollercoaster i have not mentioned that it is resistor it is conductor and a wire is also a conductor. This diagram is simple, short-circuiting of batteries, don't u think so.
     
  17. Rollercoaster

    Rollercoaster -The BlacKCoaT Operative-

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    <sarcastic>
    thatz cool... my mistake.. i thought u were familiar with electronic symbols. but u r NOT.. i saw a resister symbol and thought right, how dumb of me!
    </sarcastic>

    u have to brush up ur electronics to atleast recognising the simbles before attempting to go deep physics diving.

    see this http://en.wikipedia.org/wiki/Resistor
    (just to make myself clear the above is a hyperlink used to point to a webpage, u C L I C K on it)
     
  18. QwertyManiac

    QwertyManiac Commander in Chief

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    Looks like he had changed his question midway Rollercoaster.

    and thats creating all the confusion now.
     
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    william

    william New Member

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    i have not changed my question qwerty, question is same.
    @ rollercoaster
    another thing i know about symbols if you look clearly at the diagram then i have drawn a symbol for a resistance i accept that ,but i have marked it as a conductor. and evry conductor has resistanace and wire too is conductor.
     
  20. sariq

    sariq Guest

    @william: you should ask like that: what if I short circuit a battery?
    every wire have some resistance. in your case (short circuit) this resistance matters. current is limited by wire resistance +battery internal resistance. in your case if you neglect wire resistance current through each battery = battery voltage/battery resistance. current through central resistor is difference of these two.
     
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