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How to do this Engaa circuit in a semicircle question?

Question (+my working)

Not sure how to get the answer which is E, as I got HScreenshot_20231016-110903_Drive.jpg20231016_110738.jpg
(edited 6 months ago)
Reply 1
I think you went wrong calculation Rtotal

Cos we're just interested in the ratio of currents which will be 1/ the ratio of the restances of the paths I did...

12+9 = 21 (upper path)
15x4 = 60 (lower path)

Ratio of resistances 21/60
Ratio of currents 60/21
Reply 2
Original post by Joinedup
I think you went wrong calculation Rtotal

Cos we're just interested in the ratio of currents which will be 1/ the ratio of the restances of the paths I did...

12+9 = 21 (upper path)
15x4 = 60 (lower path)

Ratio of resistances 21/60
Ratio of currents 60/21


Oh now I get it now, since 60/21 = 20/7 = reciprocal of resistances. I got confused about the upper and lower path bit. Thanks

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