missing some basic theory

findhelporbust

Oct 14, 2005
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whatsthevoltage.JPG


i know when you put resistors in parrallel they lower in value, but is it because of voltage or current, (or is it both) going in circles, could use some help.
:-\
(beginer electronics dude here)
 

audioguru2

Apr 6, 2004
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Hi New Dude,
Neither voltage nor current goes in circles in a parallel circuit.
In your schematic, both resistors have the same voltage. The current in each one is determined by Ohm's Law (I= E/R). Their resistance in parallel Rp is also determined by Ohm's Law when you add their current into It (Rp= E/It).

If both paralleled resistors have the same value, their parallel resistance is half of one of them.
3 equal resistors in parallel = 1/3 of one of them.
4 equal resistors in parallel = 1/4 of one of them.
etc.

Just remember that resistors in parallel increases the current because thier value is approaching a short circuit that causes a very high current. ;D

 

prateeksikka

Jun 19, 2004
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just as 2 people sitting together in a restaurant have more demand for food than a single person,similarly 2 resistors in parallel extract more current from supply and thus effective resistance is lowered.
Imagine what 100 people will eat!(case of a short circuit!!)
;D

 

prateeksikka

Jun 19, 2004
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an when the food is same ,the one who is more hungry will eat up most of it.
the same is the case with a series circuit.
the lower resistance draws more current froma fixed power supply.

 

MP1

Dec 7, 2003
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findhelporbust said:
whatsthevoltage.JPG


i know when you put resistors in parrallel they lower in value, but is it because of voltage or current, (or is it both) going in circles, could use some help.
:-\
(beginer electronics dude here)
Here is a nice tutorial on series and parallel resistors that is not related to food:
http://schools.matter.org.uk/Content/Resistors/Default.htm
Hope it helps.

MP
 

V8meathead

Apr 28, 2005
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Apr 28, 2005
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Once you find the total current I(p).  And you want to find the current going through one of the two resistors.  Take... I(R1) = [R2/(R2+R1)]*I(p)  or I(R2) = [R1/(R2+R1)]*I(p).  These are called a current divider equations.

 
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bhargava

Nov 28, 2005
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Nov 28, 2005
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Hi,
Here i would like to put in some apt analogy than Food.
Electrons take lesser time to travel throgh lesser resistances like we do in lesser conjusted roads.
So more current flows through lesser resistances as current is rate of flow of electrons.
If we connect two resistors in parallel would be similar as 2 parallel conjusted roads and the total no of electrons flowing through will be sum of electrons flowing through both the resistors.
hence effective current increases for the same P.D
since R=V/I
the resistance decreases

 
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