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Question
Four resistances of 2.0Ω each are joined end to end, to form a square ABCD. Calculate the equivalent resistance of the combination between any two adjacent comers.
Solution
The diagram indicates a square ABCD formed by joining four resistances of 2Ω each, end to end.
Let us calculate the equivalent resistance of the combination B between the two adjacent comets C and D.
From given figure, arms DA, AB and BC are joined in series.
So, their equivalent of 6Ω and 2Ω are in parallel.
∴ The equivalent resistance of the combination is R.
Then, `1/"R" = 1/6 + 1/2 = 4/6 = 2/3`
∴ R = `3/2` Ω
= 1.5 Ω
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