NEET 2023 Phase 2 · PhysicsDC vs AC behaviourPrevious Year Question
For very high frequencies, the effective impedance of the circuit (shown in the figure) will be
Answer: (B) 3 Ω. Answer: (B) 3 Ω Solution: At very high frequency, X_L = ωL → ∞ (inductor blocks current, acts as an open circuit) and X_C = 1/(ωC) → 0 (capacitor acts as a short).
- A.1 Ω
- B.3 Ω✓
- C.4 Ω
- D.6 Ω
Correct Answer
(B) 3 Ω
Solution & Explanation
Answer: (B) 3 Ω Solution: At very high frequency, X_L = ωL → ∞ (inductor blocks current, acts as an open circuit) and X_C = 1/(ωC) → 0 (capacitor acts as a short). Replacing the reactive branches accordingly leaves only the resistive network, whose equivalent value is 3 Ω.
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