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Question
Two resistances when connected in parallel give resultant value of 2 ohm; when connected in series the value becomes 9 ohm. Calculate the value of each resistance.
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Solution
Let the resistances of the two resistors be x and y.
When they are connected in parallel, we have:
1 / x + 1 / y = 1 / 2 ... (1)
When they are connected in series, we have:
x + y = 9 ... (2)
On solving equations (1) and (2), we will obtain the values of the two resistors as 3 Ω and 6 Ω.
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