Total resistance in parallel circuits

AI Thread Summary
In parallel circuits, adding more resistors decreases the total resistance because it increases the number of pathways for electrons to flow. Each additional resistor provides an alternative route for current, allowing more current to flow when a voltage source is applied. This results in a higher total current and a lower effective resistance. Effective resistance and total resistance are considered the same in this context. Understanding this concept clarifies why total resistance behaves differently in parallel circuits compared to series circuits.
Hologramdr
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I understand why the total resistance in a series circuit is a total off all the resistance added together. It seems obvious because all of the electrons will have to go through all of the resistors.

Now, total resistance in a parallel circuit is really messing with my head! In a parallel circuit if you add more resistors, the total resistance goes down. I know the equation and can figure out the problems, but I don't understand **why** it happens. It seems that if you add a resistor it should resist the flow of electrons going through that part of the parallel circuit, therefore increasing the total resistance, not decreasing it. AUGH!

Can someone explain this to me?
Thanks!
 
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Adding more resistors in PARALLEL increases the number of paths for electrons to flow. Each additional path allows additional current to flow and increases the TOTAL current which will flow when a voltage source is applied to all parallel elements. Thus, the effective resistance DEcreases for parallel resistors.


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Last edited:
What is the difference between effective resistance and total resistance?
 
Hologramdr said:
What is the difference between effective resistance and total resistance?
They are the same. {Effective Resistance}={Total Resistance}.


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