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Question
Show how you would connect two 4 ohm resistors to produce a combined resistance of (a) 2 ohms (b) 8 ohms.
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Solution
Connecting two 4 Ω resistors in parallel combination:
`1/R=1/R_1+1/R_2`
`1/R=1/4+1/4`
`1/R=2/4 `
`1/R=1/2`
R=2Ω
Thus we get a 2Ω resistor.
`R=R_1+R_2`
R=4Ω+4Ω=8Ω
Thus, we will get an 8 Ω resistor.
We should connect two 4 Ωresistors in parallel to get a resistance of 8 Ω
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