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What is the resistance of R1?

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it-sall-in-th... | (Level 3) eNoter

Posted June 25, 2013 at 2:46 PM via web

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What is the resistance of R1?

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justaguide | College Teacher | (Level 2) Distinguished Educator

Posted July 6, 2013 at 6:38 AM (Answer #1)

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A potential difference of 60 V is applied across the resistor `R_1` and the two resistors in series `R_2` and `R_3` .

The current flowing through resistor `R_1` due to the voltage applied is `I_(R_1) = 60/(R_1)` . The current that flows through `R_2` and `R_3` is the same. It leads to a potential difference of 30 V across `R_2` . This gives the current `I_(R_2) = 30/(R_2)`

The total current of 2 A is the sum of `I_(R_1) = 60/(R_1)` and `I_(R_2) = 30/(R_2)` . It is not possible to solve the equation `2 = 60/(R_1) + 30/(R_2)` for a unique value of `R_1` .

The data provided is not sufficient to determine the resistance of `R_1`

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