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DC circuits

  1. Jul 25, 2008 #1
    Pertaining to DC circuits:

    a. What Phisically happens in Voltage Drop?

    b. What exactly do electrons resist against in a conductor?

    c. With batteries connected in series, why does Voltage phisically add up?

    d. With batteries connected in parallel, why does current physically add up?

    I understand the theoredic principles of these question, its just that I have a hard time grasping what actually goes on PHYSICALLY.
    Please be as Scientific and Deep as possible.
  2. jcsd
  3. Jul 26, 2008 #2
    In voltage drop, voltage is lost due to resistance in a conductor. the product of the resistance in the conductor and the current through it is the voltage drop V=IR. This works because the supply cannot variate the current therefore the voltage is proportional to the current. The electrons resist against the quantum mechanics of the electron structure as pertaining to orbitals and bond strength, hence gold and silver have the highest conductance 1/R. Voltage adds up because voltage is the change in potential charge so when two aa cells are in series you are going from 1.5V to -1.5V therefore summing to three volts. Current adds up when two batteries are in parallel because current is q/s or charge per second and the rate is increased when two sources can produce a current, where in series the internal resistance of the other power source restricts the rate of electron flow, or the current.
  4. Jul 26, 2008 #3
    This is Awesome,

    but I am still a little lost with voltage drop....and how voltage adds up in series but not in parallel. I understand the Theory behind Ohms Law but not what Physically happens in these situations.
    Last edited: Jul 26, 2008
  5. Jul 26, 2008 #4
    If you think of voltage as pressure and resistance as the diameter of a pipe, then in series the pressure is twofold but the internal resistance through the other battery decreases the current, or flow rate. and vise versa when two sources are in parallel there is less resistance to slow down the current, but there is no difference between the voltage + and voltage - so it remains at 1.5V
  6. Jul 27, 2008 #5
    Ok, I really need to rephrase this question:

    The Carrier of an Emf is in many definite/indefinite parts the net of the circuits Total Resistance (Rt). These definite/Indefinite parts are the SMALLEST degree expressed to that of a single atom, the basic Resistive properties or qualities of Itself, and the electron structure as pertaining to orbitals and bonds of Copper Atoms, or (RESISTANCE) as we call it.

    Therefore as a consequence.... the longer the carrier of an EMF, the more definite/indefinite parts or Quantum Mechanics of “Atoms” the Emf must overcome and endure to pass current equally through the Circuit, Thus Increasing the Total Resistance in respect to the Emf.

    The Carrier will be expressed as the Conductor Wire and the Conductor Load, because it carries the Emf.

    For Example: r1+r2+r3+r4+r5+r6+r7+r8+r9......ect; Consider these Atoms throughout the Entire length of Conductor Wire to the SMALLEST degree. This is the basic Resistance of each atom to an Emf that must transfer electrons through it.

    And R10+R11+R12+R13+R14+R15+R16+R17+R18......ect. Consider these also Atoms throughout the Entire length of the Conductor Load to the SMALLEST degree. This is the basic Resistance of each atom to an Emf that must transfer electrons through it.

    Copper Atoms: Which is expressed above as Lowercase r's. (The Conductor Wire)
    Aluminum Atoms: Which is expressed above as Uppercase R's. (The Conductor Load)

    First Imagine a strand of Conductive Copper Wire consisting of Single Copper atoms, followed by a strand of Conductive Load. (r1+r2+r3+r4+r5+r6+r7+r8+r9+R10+R11+R12+R13+R14+R15+R16+R17+R18)

    Now induce an Emf that is suposedly insufficient to work the Load.

    Before I can move on I need to ask these questions…………….

    1. A. What happens as a result of insufficient EMF?
    B. Does the charge die along the way? If so WHY? HOW?

    2. A. Does the insufficient Emf induce current on ANY electrons or only SOME?
    B. If some do they squash against the ones that can’t move???
    C. Is there momentarily Current only until the electrons come to a hault?
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