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Question
How would you connect two resistors in series? Draw a diagram. Calculate the total equivalent resistance.
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Solution
If current I is drawn from the battery, the current through each resistor will also be I.
On applying Ohm's law to the two resistors separately, we further
have
`"V"_1 = "I R"_1`
`"V"_2 = "I R"_2`
`"V" = "V"_1 + "V"_2`
`"IR" = "I R"_1+ "I R"_2`
`"IR" = "I " ["R"_1+ "R"_2]`
`"R" = "R"_1+ "R"_2`
Total Resistance in series R
`"R" = "R"_1+"R"_2+"R"_3`
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