Question

distingiush between resistance in cd's and resistance in parallel​

Answer 1

in series the total resistance is to simply add them

but in parallel they are added in reciprocal

Explanation:

r series = r1+r2....+rn

1/r parallel = 1/r1 + 1/r2......+1/rn

Answer 2

The difference between series and parallel circuits is that the current will split at junctions in a parallel circuit. Each unit of charge gains a certain amount of energy from the cell. It will only use that energy as it passes through a resistance. In the diagram below each orange dot represents 1C of charge, carrying 1J of electric potential. At the junction, the charges either take the right branch or continue straight. As the resistance of each branch is the same the same amount of current flows through each. Each charge does 1J of work as it passes through the resistance, meaning that the potential difference across each branch is 1V.

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