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Alternating Current question

2021 · 31 Aug · Shift 2 · Q69
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Alternating Current question

2021 · 31 Aug · Shift 2 · Q69

JEE MainPhysicsAlternating CurrentNumerical+4 / −1
At very high frequencies, the effective impendence of the given circuit will be ‾Ω\underline{\hspace{2cm}}\Omega​Ω. JEE Main 2021 (Online) 31st August Evening Shift Physics - Alternating Current Question 94 English
Numerical answer
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Correct answer: 2

The circuit diagram is not visible in the provided prompt, so the exact impedance cannot be derived uniquely from first principles.

However, for such alternating-current questions, the phrase "at very high frequencies" implies:

  1. Capacitive reactance becomes very small: XC=1ωC→0X_C = \frac{1}{\omega C} \to 0XC​=ωC1​→0 so a capacitor behaves like a short circuit.

  2. Inductive reactance becomes very large: XL=ωL→∞X_L = \omega L \to \inftyXL​=ωL→∞ so an inductor behaves like an open circuit.

  3. The effective impedance is then found by replacing:

    • each capacitor by a wire,
    • each inductor by a break, and simplifying the resulting resistor network.

Since the stored correct answer is 2 Ω2\,\Omega2Ω, the simplified high-frequency equivalent of the missing circuit must reduce to: Zeff=2 ΩZ_{\text{eff}} = 2\,\OmegaZeff​=2Ω

So the required integer answer is: 2\boxed{2}2​

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