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Question
Two cells each of 5V are connected in series across an 8Ω resistor and three parallel resistors of 4Ω, 6Ω, and 12Ω. Draw a circuit diagram for the above arrangement. Calculate
- the current drawn from the cell
- current through each resistor
Solution
i) Current drawn from the cell
Eeq = 5+5 = 10V
Reff = Rs+ Rp
Rs = 8 Ω
`1/"R"_"p" = 1/4 + 1/6 + 1/12`
`= (18 + 12 + 6)/72 = 36/72`
∴ Rp = `72/36` = 2 Ω
Reff = 8 + 2 = 10Ω
I = `"E"_"eq"/"R"_"eff" = 10/10 = 1`A
∴ I = 1A
Voltage drop V= IR =1 × 2 = 2V
V = 2V
ii) Current through each resistor:
∴ current in 4Ω resistor
I = 24 = O.5A
I = O.5A
current in 6Ω resistor, I = `2/6` = 0.33 A
I = 0.33A
current in 12Ω resistor, I = `2/12 = 1/6` = 0.17A
I = 0.17A
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