Derive an expression for delta to star transformation.

Derive an expression for delta to star transformation. 
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1 Answer

Answer :

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For delta network the resistance between the terminals 1 and 2 consists of R12 in parallel with 

(R23+R31) Hence ,the resistance between the terminals 1 and 2 is

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In case of star network the resistance between the terminals 1 and 2 is=R1+R2,so we get

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Subtracting equation( ii) from( i),we get

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Adding equations (iii) and( iv),we have 

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