Identifying series and parallel connections

In summary: Yes, you are correct. My apologies for the confusion. I was not thinking clearly when I wrote that. You are right that the blue components are not in series because there are more than two components connected to that wire segment.
  • #36
In (1) all 1,2,3 are in series but in (2) only 2 and 3 are in series but 1 and 2 and 1 and 3 are not in series,right?
 
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  • #37
gracy said:
In (1) all 1,2,3 are in series but in (2) only 2 and 3 are in series but 1 and 2 and 1 and 3 are not in series,right?
I don't know what you are referring to. What are (1) and (2) ?
 
  • #38
In (1) all 1,2,3 are in series but in (2) only 2 and 3 are in series but 1 and 2 and 1 and 3 are not in series,right?
1234.png
 
  • #39
gneill said:
I don't know what you are referring to. What are (1) and (2) ?
Sorry!I clicked on post reply reply but was intended to click on upload!
 
  • #40
Here no components are in series,Right?
O.png

Sorry if my resistor looks odd!:smile:
 
  • #41
In (1) all three components are in series, yes.

In (2) capacitor 2 and resistor 3 are in series, yes, but they are also in series with the capacitor that you've placed at the bottom. Resistor 1 is not in series with anything, in fact it is "shorted out" by the wiring that connects both of its ends.
 
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  • #42
gneill said:
in fact it is "shorted out" by the wiring that connects both of its ends.
Now what is shorted out!Are not you afraid of opening a brand new topic:smile:

On a serious note I want to ask one thing
How do you decide to bring new wire in I mean switching to yellow from blue,I faced this problem while drawing circuits in post #38 and #40.
 
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  • #43
gracy said:
Here no components are in series,Right?
View attachment 92486
Sorry if my resistor looks odd!:smile:
Two resistors are in series, but they are shorted out (bypassed) by the red path joining their outer ends.

Gracy, it should not be necessary to enumerate every possible permutation of connections in order to understand the concept. If there is a single, undivided path for current to follow through a set of components then they are in series. If current has optional paths through other components anywhere along the way then they are not in series.
 
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  • #44
gneill said:
Two resistors are in series,
But I can see only one
that is
ab.png
 
  • #45
gracy said:
Now what is shorted out!Are not you afraid of opening of a brand new topic:smile:
"shorted out" means that there is a low (usually zero) resistance path bypassing a circuit or portion of a circuit. It's a "short path" for the current to follow rather than flow though the circuit.
On a serious note I want to ask one thing
How do you decide to bring new wire in I mean switching to yellow after blue,I faced this problem while drawing circuits in post #38 and #40.
I've explained that a node is isolated, contiguous wiring. If you follow a continuous wire path between two points, then they belong to the same node.

Each colored "island" in the diagram is contiguous wiring.
 
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  • #46
gracy said:
But I can see only one
that is
View attachment 92487
a and b are each resistors. That makes two resistors. They are in series.
 
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  • #47
Now I think I have got what is series connection .And the credit goes to definitely you!
I want to understand about parallel connection now!
gneill said:
No, only two components can be connected to any node along a series-connected path.
What happens in parallel connection?
 
  • #48
gracy said:
Now I think I have got what is series connection .And the credit goes to definitely you!
I want to understand about parallel connection now!

What happens in parallel connection?
Things that are in parallel have the same potential difference because they all connect to the same pair of nodes. Is that what you mean?
 
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  • #49
gneill said:
only two components can be connected to any node along a series-connected path.
Is not this applicable for parallel connections?
 
  • #50
gracy said:
Is not this applicable for parallel connections?
No, any number of components can be in parallel and share the same pair of nodes (only two nodes are required for any number of parallel components).

Any number of components can be in series, too, but every pair of them along the series connected path requires an isolated node for their connection.
 
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  • #51
gneill said:
No, any number of components can be in parallel and share the same pair of nodes (only two nodes are required for any number of parallel components).
Here node implies highlighted pink portion "A "or complete blue portion(if we refer image in post #17)
 
  • #52
gracy said:
Here node implies highlighted pink portion "A "or complete blue portion(if we refer image in post #17)
As an example, yes. The blue wire segment is one node. The red wire segment is another node. The highlighted pink portion is just a portion of the blue node, it is not a separate node.

Components that share both of those nodes (red, blue) for their connections are in parallel.
 
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  • #53
By isolated node (that you used in explanation of series connection)means
orange portion "a" here
it appears like a single line
portion.png
 
  • #54
Resistors 1,2,3,4, and 5 are in parallel connection.
 
  • #55
Resistors 1,2,3,4, and 5 are in parallel connection.
para.png

And there are no other components in parallel connection.
Right?
 
  • #56
gneill said:
Gracy, it should not be necessary to enumerate every possible permutation of connections in order to understand the concept.
Sorry but it gives me confident to move further.As I am satisfied that till here my all concepts are clear and I should move forward.
 
  • #57
gracy said:
Resistors 1,2,3,4, and 5 are in parallel connection.
View attachment 92490
And there are no other components in parallel connection.
Right?
Correct.
 
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  • #58
please answer my post #53 :smile:
 
  • #59
gracy said:
By isolated node (that you used in explanation of series connection)means
orange portion "a" here
it appears like a single line
View attachment 92489
No, it is not isolated. It is a small portion of the larger whole (blue network) which has other connections.
 
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  • #60
gracy said:
On a serious note I want to ask one thing
How do you decide to bring new wire in I mean switching to yellow from blue,I faced this problem while drawing circuits in post #38 and #40.
gneill said:
I've explained that a node is isolated, contiguous wiring. If you follow a continuous wire path between two points, then they belong to the same node.

Each colored "island" in the diagram is contiguous wiring.
Based on my observation of our diagram
A node can not cross any component,right?
I mean it will be wrong if I will replace green wire with yellow wire because by doing thatyellow wire will crss the component(battery)
yellow.png
 
  • #61
Correct.
 
  • #62
gneill said:
No, it is not isolated. It is a small portion of the larger whole (blue network) which has other connections.
Oh,yes.
But I think it should be correct that
isolated node appears like a single line(linear; no branches)
 
  • #63
gneill said:
Correct.
Was it the answer of my post#60?
 
  • #64
gracy said:
Oh,yes.
But I think it should be correct
isolated node appears like a single line(linear; no branches)
Shape, angle, length, etc., make no difference. Isolated means no way out except via a component. Contiguous wires, bounded only by components, are a single node.
 
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  • #65
gracy said:
Was it the answer of my post#60?
Yes.
 
  • #66
And a node will continue until any component comes in it's way .I mean it would be wrong if I will replace blue with yellow wire like this

replace.png


If my constant questions are bothering you,please answer them later.I am ready to wait.:smile:
 
  • #67
gracy said:
And a node will continue until any component comes in it's way .I mean it would be wrong if I will replace blue with yellow wire like this
Yes. That would be wrong.
 
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  • #68
gneill said:
"shorted out" means that there is a low (usually zero) resistance path
When we say components are shorted out in spite of presence of some (non zero )resistance?when there is resistance of 0. something ohm?Or sometimes even 1 or 2 ohms of resistance ?
My friend says even if there is 1 or 3 ohms of resistance the components are shorted out.I am asking for theoretical purpose (on paper)not laboratory.
My actual question is what is low resistance?Range for low resistance?
 
  • #69
gracy said:
When we say components are shorted out in spite of presence of some (non zero )resistance?when there is resistance of 0. something ohm?Or sometimes even 1 or 2 ohms of resistance ?
My friend says even if there is 1 or 3 ohms of resistance the components are shorted out.I am asking for theoretical purpose (on paper)not laboratory.
My actual question is what is low resistance?Range for low resistance?
Technically a "short circuit" is any path that bypasses an intended or normal path of a circuit. It diverts current that would otherwise flow through the intended path when the circuit is operating normally. The particular value of the shorting resistance is technically unimportant.

However, it is common to speak of a short circuit as usually being of zero resistance, since placing a wire across a portion of a circuit to aid in analysis of the circuit is a common practice and is referred to as "shorting" the component or path. So it is common to think of a short circuit as being a zero resistance path unless otherwise specified.

"Low resistance" is a relative term. It implies low with respect to the other resistances in the surrounding circuit. There's no strict definition. You can take it to mean any value that would measurably alter the operating behavior of a circuit.
 
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  • #70
If there is 4 ohm resistance in an intended or normal path of a circuit and there is an optional path where 3 ohm resistance is present.Then current will take route where there is 3 ohm resistance.Will it be called short circuit or greater difference in resistance is required?
 
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