Prove 1/P = 1/P1 + 1/P2

Proof:

|(R1)(R2)|

Let the resistances be R1 , R2 connected in series. And the potential difference be V ;

We know that :

P1 = V²/R1 (1) and

P2 = V²/R2 (2)

In series combination , the net resistance is the algebraic addition of individual resistance :

R = R1 + R2

=> V²/P = V²/P1 + V²/P2

=> 1/P = 1/P1 + 1/P2

Explanation:

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