Identical bulbs, rank by brightness

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Bulbs A and C are in series, making them equally bright, while bulb B is not connected to the negative terminal of the battery, resulting in no current passing through it. The correct ranking of brightness is A = C > B. The discussion clarifies that since B is part of an open circuit, it cannot receive current. Participants express confusion about the interpretation of brightness rankings but ultimately agree on the reasoning. A closed circuit is necessary for current flow, which is why bulb B remains unlit.
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Homework Statement


Which bulb(s) will have the higher light intensity?

Homework Equations


Resistors:
Connection in series: same current
Connection in parallel: same delta V

The Attempt at a Solution


A and C are in series. They'll be equally bright. B is not connected to the negative terminal of the battery. no current will pass through it. Hence A=B>C
 
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kamhogo said:

Homework Statement


Which bulb(s) will have the higher light intensity?

Homework Equations


Resistors:
Connection in series: same current
Connection in parallel: same delta V

The Attempt at a Solution


A and C are in series. They'll be equally bright. B is not connected to the negative terminal of the battery. no current will pass through it. Hence A=B>C
 
I agree with your answer and reasoning.
 
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kamhogo said:
Hence A=B>C
huh ?
 
phinds said:
huh ?
Incorrect??
 
kamhogo said:
Incorrect??
well, what do you mean by it? What it says to me is very literal, A equals B and either both are greater than C or at least B is greater than C. I don't see how you get that from what's going on. Do you mean something else?
 
phinds said:
well, what do you mean by it? What it says to me is very literal, A equals B and either both are greater than C or at least B is greater than C. I don't see how you get that from what's going on. Do you mean something else?
I mean that A and B are equally bright and that both are brighter than C
 
kamhogo said:
I mean that A and B are equally bright and that both are brighter than C
Yes, that's what I thought. Is that really what's happening?
 
phinds said:
Yes, that's what I thought. Is that really what's happening?
Sorry, I was confused. I meant A=C>B. Also, is there any current passing through B at all?
 
  • #10
kamhogo said:
Sorry, I was confused. I meant A=C>B.
Yes, that makes sense.

Also, is there any current passing through B at all?
what do you think?
 
  • #11
phinds said:
Yes, that makes sense.

what do you think?
I think there's no current passing through B at all. My reasoning: why would the electrons go through path with a resistor that does not lead to the negative terminal of the battery when they have the choice to take a resistless (ideally) path that leads to the negative terminal of the battery.
 
  • #12
kamhogo said:
I think there's no current passing through B at all. [/color]

My reasoning: why would the electrons go through path with a resistor that does not lead to the negative terminal of the battery when they have the choice to take a resistless (ideally) path that leads to the negative terminal of the battery.
I don't understand this. Can you explain?
 
  • #13
kamhogo said:
I think there's no current passing through B at all. My reasoning: why would the electrons go through path with a resistor that does not lead to the negative terminal of the battery when they have the choice to take a resistless (ideally) path that leads to the negative terminal of the battery.
Your answer is correct. Have you studied what an "open circuit" is?
 
  • #14
cnh1995 said:
Your answer is correct. Have you studied what an "open circuit" is?
Not yet, but I am curious. I'll look it up. Is it when there is a gap somewhere on the circuit so the current pass? What is it useful for?
 
  • #15
kamhogo said:
Not yet, but I am curious. I'll look it up. Is it when there is a gap somewhere on the circuit so the current pass? What is it useful for?
It is the technical term for a "gap" in the circuit, so current can't flow through it.
A circuit needs to be closed for the flow of current. Here, no current flows through bulb B since there's no closed path.
 
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