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प्रश्न
Show by a diagram how two resistors R1 and R2 are joined in parallel. Obtain an expression for the total resistance of the combination.
उत्तर
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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