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Question
Three resistors 2 Ω, 4 Ω and 5 Ω are combined in parallel. What is the total resistance of the combination?
Solution
There are three resistors of resistances,
R1 = 2 Ω, R2 = 4 Ω, and R3 = 5 Ω
They are connected in parallel. Hence, total resistance (R) of the combination is given by,
`1/"R" = 1/"R"_1 + 1/"R"_2 + 1/"R"_3`
= `1/2 + 1/4 + 1/5`
= `(10 + 5 + 4)/20`
= `19/20`
∴ R = `20/19` Ω
Therefore, the total resistance of the combination is `20/19` Ω.
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