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Saturday, 31 October

JEE Main 2021 · PhysicsNumerical answerNumerical valueHardMulti-step

JEE Main 31 August 2021, Shift 2, Physics Q28

Question 28 of 90 in this shift, Physics question 28 of 30, Section B.

At very high frequencies, the effective impedance of the given circuit will be ________ Ω\Omega.

The figure, in words

AC circuit with a 220 V source (~) in the bottom wire. Upper branch: 1 Ω resistor in series with a 0.5 F capacitor, then a node, then a 2 Ω resistor in series with a 0.5 F capacitor. Lower branch: 1 Ω resistor in series with a 20 H inductor, then a node, then a 2 Ω resistor in series with a 0.5 F capacitor. A 0.5 F capacitor is connected vertically between the upper and lower middle nodes. The left and right ends of the two branches are joined to the source through the outer wires.

Official answer

2

NTA final key.

Chapter
Alternating Current
Topic
Phasor Diagrams
Idea tested
Frequency Variation in RC Phasors

Same topic in other shifts

All Phasor Diagrams questions
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  5. 4 Apr 2025, Shift 2 · Q48An inductor of self inductance 1 H is connected in series with a resistor of 100 π100\,\pi ohm and an ac supply of 100 π100\,\pi volt, 50 Hz.…MediumNumerical value
  6. 7 Apr 2025, Shift 1 · Q49For ac circuit shown in figure, R = 100 kΩ\Omega and C = 100 pF and the phase difference between Vin\mathrm{V_{in}} and…HardNumerical valueHas a figure

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. This question needs a figure we do not reproduce; it is described in words above. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.