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Current electricity 
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#1
Mar710, 04:52 AM

P: 188

why is current always same for series resistances i mean if a current passes through a resistor a then same current will pass through resistor b does the first resistor not reduces current



#2
Mar710, 06:03 AM

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#3
Mar710, 06:04 AM

PF Gold
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Current is the flow of electrons, voltage tells us something about the force on the electrons.
The flow through the whole series is affected by both resistors all at once. The voltage drops with each resister in series. 


#4
Mar710, 10:11 AM

P: 188

Current electricity



#5
Mar710, 10:22 AM

P: 513

If the current in series combination isn't same everywhere, there'd be accumulation of free electrons at some place and the wire would go on charging up, but the wire must be electrically neutral, and there's no good reason for this not to be true unless in relative motion



#6
Mar710, 11:40 AM

P: 5,462

I think this is a perfectly reasonable query for a beginner to make.
This is where the hydraulic analogy is appropriate (please don't spoil this thread with discussion other failings of this analogy) Imagine that your series resistors are like pipes, one after the other. If you keep pumping water into one end it has to come out of the other or burst the pipes. Of course the longer the pipes the harder you have to pump to push the water through. Resistors are like this, if you push current into one end it has to come out of the other. Of course the is something which is lost in passing the resistor. This is the voltage. The greater the resistance the greater the voltage loss. 


#7
Mar710, 01:09 PM

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#8
Mar810, 12:56 PM

P: 188




#9
Mar810, 02:45 PM

P: 5,462

I deliberately didn't mention the pipe diameter, I said longer.
But yes a smaller diameter pipe offers greater resistance to flow than a larger one so you have to pump harder to push the flow through. Buckethead had a slightly different interpretation of you post and thinking about it he might have been right. I though you meant putting one resistor after another (hence my comment about pipes). This is called a series circuit and since there is only one path available all the current that flows into the first resistor , flows out and into the second one and so on, like water in the pipes. Alternatively if you meant that you have one resistor connected to a supply (battey etc) and you change it for a different one will you get a different current, the answer is yes. The battery voltage will not change (within reason) but the current depends upon the total resistance seen by the battery. 


#10
Apr2910, 12:35 AM

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#11
Apr2910, 05:36 AM

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Yes.



#12
Apr3010, 05:41 AM

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#13
Apr3010, 06:50 AM

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