Question

the value of two resistance R1 equals to 5 + - 0.3 on 8 is equal to 10 plus minus 0.2 on the percentage error in the equivalent resistance when they are connected in series​

Answer 1

Explanation:

This'll require some basic understanding of the relation between errors and calculus. For any quantity A , |dA/A| is the relative error (or percentage error if multiplied with 100). So, knowing the relevant equation (here, 1/R=1/r1+1/r2 , R being the effective resistance in parallel and r1 and r2 being the individual resistances), we can differentiate both the sides to get the expression for the relative error of the target quantity. See the working below, to get the percentage error as 3%.

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