JEE Main 2021 · PhysicsNumerical answerNumerical valueEasyCalculation

JEE Main 25 February 2021, Shift 1, Physics Q27

Question 27 of 90 in this shift, Physics question 27 of 30, Section B.

A transmitting station releases waves of wavelength 960 m. A capacitor of

2.56\ \mu

F is used in the resonant circuit. The self inductance of coil necessary for resonance is __________

\times10^{-8}

Official answer

NTA final key.

Chapter: Alternating Current
Topic: LCR Resonance
Idea tested: Resonant Frequency Calculation

Same idea in other shifts

Asked 9× in all

5 Apr 2026, Shift 2 · Q48A series LCR circuit with $R=20\ \Omega$ , $L=1.6$ H and $C=40\ \mu\mathrm{F}$ is connected to a variable frequency a.c. source. The…EasyNumerical value
6 Apr 2024, Shift 2 · Q59For a given series LCR circuit it is found that maximum current is drawn when value of variable capacitance is 2.5 nF. If resistance of…EasyNumerical value
1 Feb 2024, Shift 1 · Q43In series LCR circuit, the capacitance is changed from C to 4C. To keep the resonance frequency unchanged, the new inductance should be :EasySingle correct
25 Jul 2022, Shift 1 · Q42To increase the resonant frequency in series LCR circuit,EasySingle correct
28 Jun 2022, Shift 1 · Q60A telegraph line of length 100 km has a capacity of 0.01 $\mu$ F/km and it carries an alternating current at 0.5 kilo cycle per second. If…EasyNumerical value
29 Jun 2022, Shift 2 · Q60An inductor of 0.5 mH, a capacitor of 200 μF and a resistor of 2 Ω are connected in series with a 220 $V$ ac source. If the current is in…EasyNumerical value
26 Feb 2021, Shift 2 · Q18Find the peak current and resonant frequency of the following circuit (as shown in figure).MediumDiagram basedHas a figure
25 Jul 2021, Shift 2 · Q25Two circuits are shown in the figure (a) & (b). At a frequency of __________ rad/s the average power dissipated in one cycle will be same…MediumNumerical 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. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.