NEET 2020 · PhysicsCapacitive reactancePrevious Year Question
A 40 μF capacitor is connected to a 200 V, 50 Hz ac supply. The rms value of the current in the circuit is, nearly:
Answer: (A) 2.5 A. Answer: (A) 2.5 A Solution: Angular frequency ω = 2πf = 2π(50) = 100π rad/s.
- A.2.5 A✓
- B.25.1 A
- C.1.7 A
- D.2.05 A
Correct Answer
(A) 2.5 A
Solution & Explanation
Answer: (A) 2.5 A Solution: Angular frequency ω = 2πf = 2π(50) = 100π rad/s. Capacitive reactance X_C = 1/(ωC) = 1/(100π × 40×10⁻⁶) = 1/(4π×10⁻³) ≈ 79.6 Ω. RMS current I_rms = V_rms/X_C = 200/79.6 ≈ 2.51 A ≈ 2.5 A.
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