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Physics - Total Resistance

In the OCR G482 June 2016 Paper, question 2b)iii has me a bit confused...
I know the question tells you all of the resistors are in parallel, but could someone explain to me exactly why each of the resistors in the 8 shape are in parallel...?

I will be extremely grateful for any help...
Thank you!

Here is a link to the paper:

http://pmt.physicsandmathstutor.com/download/Physics/A-level/Past-Papers/OCR-Old/Unit-2/June%202016%20QP%20-%20Unit%202%20OCR%20Physics%20A-level.pdf
Original post by Bulbasaur10
In the OCR G482 June 2016 Paper, question 2b)iii has me a bit confused...
I know the question tells you all of the resistors are in parallel, but could someone explain to me exactly why each of the resistors in the 8 shape are in parallel...?

I will be extremely grateful for any help...
Thank you!

Here is a link to the paper:

http://pmt.physicsandmathstutor.com/download/Physics/A-level/Past-Papers/OCR-Old/Unit-2/June%202016%20QP%20-%20Unit%202%20OCR%20Physics%20A-level.pdf


You've seen 7 segment displays like that before I'm sure...
in order to operate properly and display different numerals the segments need to be individually switchable - which isn't possible with them in series - if the segments were in series it'd only be capable of showing the numeral 8 (all segments lit) or blank (all segments unlit)
Original post by Joinedup
You've seen 7 segment displays like that before I'm sure...
in order to operate properly and display different numerals the segments need to be individually switchable - which isn't possible with them in series - if the segments were in series it'd only be capable of showing the numeral 8 (all segments lit) or blank (all segments unlit)


Thank you that makes sense. Although I still don't know how you would be able to tell they were in parallel just by looking at a circuit diagram for one of them as to me, and this probably sounds stupid, a couple of them look like they are in series. I have seen seven segment displays before yes but I would rather ask now and feel dumb than not ask and get it wrong in the exam. :frown:
Original post by Bulbasaur10
Thank you that makes sense. Although I still don't know how you would be able to tell they were in parallel just by looking at a circuit diagram for one of them as to me, and this probably sounds stupid, a couple of them look like they are in series. I have seen seven segment displays before yes but I would rather ask now and feel dumb than not ask and get it wrong in the exam. :frown:


I feel like I'm looking at it wrong and assuming for some reason that the resistors are connected up only along the lines of the 8 but that this is not the case.
Original post by Bulbasaur10
I feel like I'm looking at it wrong and assuming for some reason that the resistors are connected up only along the lines of the 8 but that this is not the case.


The arrangement of current limiting resistors and switches looks like this...



The LED connections inside the unit could either be common cathode or common anode...



Original post by Joinedup
The arrangement of current limiting resistors and switches looks like this...



The LED connections inside the unit could either be common cathode or common anode...





Thank you so much! I feel like I was totally misunderstanding something key... which I was... Oh well I know it now!

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