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Question
Study the following circuit and find:
- Effective resistance of the circuit
- Current drawn from the battery
- Potential difference across the 5 omega resistor
Solution
(i) Effective resistance of the circuit
R3 and R4 are in series and both are parallel to R2
R3 + R4 = 10 Ohm
Effective Resistance across R2 (R')
`1/("R'") = 1/"R"_2 + 1/("R"_3 + "R"_4)`
R' = 5 Ohm
Now, R1', R' and R5 are in series
Effective resistance of the circuit = R1 + R' + R5
= 5 + 5 + 10
= 20 Ohm
(ii) Current drawn from battery
V = IR
I = `"V"/"R"`
I = `20/20`
I = 1 A
(iii) Potential difference across 5-ohm resistor
V = IR
V = 1 × 5
V = 5V
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