Battery connected to an infinite number of loads in parallel

AI Thread Summary
A battery with internal resistance and voltage is connected to an infinite number of identical lightbulbs in parallel. The current through the first lightbulb can be calculated using the total current divided by the number of bulbs, leading to the factor of 1/N. The confusion arises from the assumption that current distribution is not even, but in this case, it is because all branches are identical. The correct approach confirms that the current splits evenly among the parallel loads. Understanding this principle clarifies the solution to the problem.
032050
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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 I am doing the question I'm out by a factor of N being the number of lights attached.


Homework Equations


V=IR
1/Rparallel=[1/R1+1/R2...]^-1
Rt=Rparallel+r

The Attempt at a Solution


Okay so i know that i can condense all the parallel loads to
Rparallel=(R/N)
then current through the first bulb would be I=V/(r+R/N)
except the solution has the I=1/N[V/(r+R/N)]

I have no idea where that 1/N factor came from, I've tried everything, almost i guess...
Thanks a lot in advance
 
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032050 said:
Okay so i know that i can condense all the parallel loads to
Rparallel=(R/N)
OK.
then current through the first bulb would be I=V/(r+R/N)
That's the total current through all the bulbs.
 
If I take 1/N of the total current and say that that is going through the first bulb is that not assuming that the current is evenly distributed to all the loads. whenever I have done questions where the current splits into two directions it hasn't been an even distribution of the current?
 
032050 said:
If I take 1/N of the total current and say that that is going through the first bulb is that not assuming that the current is evenly distributed to all the loads.
Yes.
whenever I have done questions where the current splits into two directions it hasn't been an even distribution of the current?
If each branch is identical--as is the case here--why shouldn't the current split evenly?
 
Oh I never thought of that okay thanks a lot!
 
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