In a circuit, three resistors of 2 Ω, 3 Ω, and 6 Ω are connected in parallel across a 12 V battery with internal resistance 1 Ω. The current through the 3 Ω resistor is:
Correct answer: A. 2A
- A. 2A
- B. 3A
- C. 4A
- D. 5A
Explanation
Equivalent resistance of parallel resistors: 1/Rₚ = 1/2 + 1/3 + 1/6 = 3/6 + 2/6 + 1/6 = 1, so Rₚ = 1 Ω. Total resistance = Rₚ + r = 1 + 1 = 2 Ω. Total current Iₜₒₜₐₗ = V/Rₜₒₜₐₗ = 12/2 = 6 A. Voltage across parallel resistors = V - Ir = 12 - 6 × 1 = 6 V. Current through 3 Ω resistor = V/R = 6/3 = 2 A.
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