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Question
Three resistors are connected to a 12 V battery as shown in the figure given below:

(i) What is the current through the 8 ohm resistor?
(ii) What is the potential difference across the parallel combination of 6 ohm and 12 ohm resistor?
(iii) What is the current through the 6 ohm resistor?
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Solution
(i) 6 ohm and 12 ohm are connected in parallel, So
⇒ `1/"R"_1 = 1/6 + 1/12 = (2 + 1)/12 = 3/12`
⇒ `1/"R"_1 = 1/4`
R1 = 4 ohm.
∴ Total Resistance R = 8 + 4 = 12 ohm.
Now ∵ V = IR
⇒ 12 = I × 12
∴ I = 1 Amp.
(ii) V = IR = 1 ×4 = 4 Volt
(iii) ∵ V = I1R
⇒ 4 = I1 × 6
∴ I1 = `4/6`
= 0.66 Amp.
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