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Question
A resistor of 8 ohms is connected in parallel with another resistor X. The resultant resistance of the combination is 4.8 ohms. What is the value of the resistor X?
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Solution
When the two resistors are connected in parallel, we have:
`1/R=1/R_1+1/R_2`
`1/4.8=1/8+1/x`
`1/4.8-1/8=1/x`
`(1-0.6)/4.8=1/x`
`0.4/4.8=1/x`
`x=12`Ω
`x=12`Ω
Therefore, the value of X=12 I
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