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JEE PHYSICS MCQ: ALTERNATING CURRENT

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Analyzing +4 | -1
An AC source producing emf

e=e0[cos⁡(100πs−1)t+cos⁡(500πs−1)t]e=e_0\left[\cos \left(100 \pi \mathrm{s}^{-1}\right) t+\cos \left(500 \pi \mathrm{s}^{-1}\right) t\right]

is connected in series with a capacitor and resistor. The steady state current in the circuit is found to be

I=I1cos⁡[(100πs−1)t+ϕ1]+I2cos⁡[(500πs−1)t+ϕ2]I=I_1 \cos \left[\left(100 \pi \mathrm{s}^{-1}\right) t+\phi_1\right]+I_2 \cos \left[\left(500 \pi \mathrm{s}^{-1}\right) t+\phi_2\right]
View answer and explanation
Correct option: C
I1<I2I_1 < I_2
Option C (I1<I2I_1 < I_2) is correct because the impedance is lower at higher frequencies in a capacitor circuit, leading to a larger current.

More Questions from ALTERNATING CURRENT

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In a series RC circuit with an AC source, R=300 ΩR=300 \, \Omega, C=25 μF,ε0=50 VC=25 \, \mu \mathrm{F}, \varepsilon_0=50 \mathrm{~V} and v=50/π Hzv=50 / \pi \, \mathrm{Hz}. Find the peak current and the average power dissipated in the circuit. In a series circuit R=300Ω,L=0.9 H,C=2.0R=300 \Omega, L=0.9 \mathrm{~H}, C=2.0 μF\mu F and ω=1000 rad/sec\omega=1000 \mathrm{~rad} / \mathrm{sec}. The impedance of the circuit is: An L-C-R series circuit with a resistance of 100Ω100 \Omega is connected to 200 V200 \mathrm{~V} (AC source) and angular frequency 300 rad/s300 \, \mathrm{rad} / \mathrm{s}. When only the capacitor is removed, then the current lags behind the voltage by 60∘60^{\circ}. When only the inductor is removed the current leads the voltage by 60∘60^{\circ}. The average power dissipated in original L-C-R circuit is Assertion (A) : In series L−C⋅R,ACL-C \cdot R, \mathrm{AC} circuit, current and voltage are in same phase at resonance.

Reason (R) : In series L−C−R,ACL-C-R, \mathrm{AC} circuit, resonant frequency does not depend on the value of resistance. Hence, current at resonance does not depend on resistance.
A series L−C−RL-C-R circuit is connected to an AC\mathrm{AC} voltage source. When LL is removed from the circuit, the phase difference between current and voltage is π4\frac{\pi}{4}. If instead CC is removed from the circuit, the phase difference is again π4\frac{\pi}{4} between current and voltage. The power factor of the circuit is A capacitor in an ideal LC circuit is fully charged by a DC source. Then it is disconnected from DC source, the current in the circuit
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