LC Oscillations

IMPORTANT

LC Oscillations: Overview

This topic covers concepts such as L-C Oscillator Circuit, Comparison of L-C Oscillations with Spring Block Oscillations, Frequency of L-C Oscillator Circuit, Comparison between Self Inductance and Inertia, etc.

Important Questions on LC Oscillations

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The current through a coil of self-inductance L=2mH is given by i=t2e-t at time t. How long it will take to make the emf zero?

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When current in coil changes from 5 A to 2 A in 0.1 s, an average of 50 V is produced. The self-inductance in HenryH of the coil is n3. Write the value of n.

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A capacitor of capacity 2μF is charged to a potential difference of 12 V. It is then connected across an inductor of inductance 0.6mH. What is the current (in mA) in the circuit at a time when the potential difference across the capacitor is 6.0 V?

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What is LC oscillation?

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A circuit consists of a coil with inductance L and an uncharged capacitor of capacitance C. The coil is in a constant uniform magnetic field such that the flux through the coil is ϕ. At time t=0 min, the magnetic field is abruptly switched OFF. Let ω0=1LC and ignore the resistance of the circuit. Then,

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The resonance frequency of LC circuit is

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A 60μF capacitor is charged to 100 volts. This charged capacitor is connected across a 1.5mH coil, so that LC oscillations occur. The maximum current in the coil is:-

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In the AC network shown in figure, the rms current flowing through the inductor and capacitor are 0.6 A and 0.8 A respectively. Then the current coming out of the source is

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A 60 μF capacitor is charged to 100 volts. This charged capacitor is connected across a 15 mH coil, So that LC oscillations occur. Maximum current in the coil is :

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A fully charged capacitor C with initial charge q0 is connected to a coil of self inductances L at t = 0. The time at which the energy is stored equally between the electric and the magnetic fields is :

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In an LC circuit shown in figure, C=2 F and L=2 H. At time t=0, charge on the capacitor is 3 coulomb and it is decreasing with rate of 4 C s-1. Then choose the correct statement.

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Two capacitors of capacitance C1 and C2 are charged to a potential difference of V1 and V2 respectively and are connected to an inductor of inductance L as shown in the figure. Initially key k is open. Now key k is closed and current in the circuit starts increasing. When current in the circuit is maximum

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For the circuit shown in the figure, the current through the inductor is 0.6 A, while the current through the capacitor is 0.4 A. The current drawn from the generator is:

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In following L-C circuit at t=0, charge on capacitor qmax=200μC, what is dIdt when q=100 μC

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The natural frequency of the circuit is (in rad s-1),

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In series LCR resonant circuit if both L and C are increased by 20% then new resonant frequency:-

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An LC current contains inductance L=1 μH and capacitance C=0.01 μF. The wavelength of electromagnetic wave generated is nearly :-

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The resonant frequency of the L-C circuit is f0 before insertion of the dielectric of εr=16. After inserting the dielectric, the resonant frequency will be :-

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In an L-C circuit which of the following is true at t=3T4(T is the time period of oscillation)? Assume that at t=0 the capacitor is fully charged and the current in the circuit is zero.

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The inductor in a L-C oscillation has a maximum potential difference of 16 V and maximum energy of 640 μJ. find The value of capacitance in L-C circuit .