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Question
Show by a diagram how two resistors R1 and R2 are joined in parallel. Obtain an expression for the total resistance of the combination.
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Solution
On applying Ohm's law to the two resistors separately, we further
Have
`"I"_1 = "V" / "R"_1`
`"I"_2 = "V" / "R"_2`
`"I" = "I"_1 + "I"_2 `
`"V"/"R" = "V"/"R"_1+ "V"/"R"_2`
`1/"R"=1/"R"_1+1/"R"_2`
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