# Capacitance from plates

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## Homework Statement

Five plates with same area are placed as in figure. Distance between any 2 consecutive plates is d. Find equivalent capacitance(ab). (Note-Answer is given as 5C/3, in terms of C so I suppose C is capacitance of a +ve and -ve plate separated by d). The lower letter is A, it is marked positive and upper letter is B marked negative.

All related.

## The Attempt at a Solution

numbering 1 to 5 from top to bottom. I can see 1 capacitor due to negative 2 and positive 3 and none else since 1 and 4 are uncharged so answer should be C...unless charges get induced. In that case there are 4 capacitors and answer should be 4C. I'd be grateful for some help.

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I only have a inbuilt webcam...please pardon the poor quality. I'll post another one however, I've provided all information and the general outline of the figure should be enough...

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CWatters
Homework Helper
Gold Member
Try drawing an equivalent circuit. It should have four capacitors on it, one per gap.

The top plate and forth plate are connected together. I recommend labeling that connection node C.

Krushnaraj Pandya
Gold Member
Try drawing an equivalent circuit. It should have four capacitors on it, one per gap.

The top plate and forth plate are connected together. I recommend labeling that connection node C.
Got it! That was very neat. Thank you very much for your help.