Alternating Current · Physics · JEE Advanced
MCQ (Single Correct Answer)
A circuit with an electrical load having impedance $Z$ is connected with an AC source as shown in the diagram. The source voltage varies in time as $V(t)=300 \sin (400 t) \mathrm{V}$, where $t$ is time in s . List-I shows various options for the load. The possible currents $i(t)$ in the circuit as a function of time are given in List-II.
Choose the option that describes the correct match between the entries in List-I to those in ListII.
| List–I | List–II |
|---|---|
(P)  |
(1)  |
(Q)  |
(2)  |
(R)  |
(3)  |
(S)  |
(4)  |
(5)  |
The circuit shown in the figure contains an inductor $L$, a capacitor $C_0$, a resistor $R_0$ and an ideal battery. The circuit also contains two keys $\mathrm{K}_1$ and $\mathrm{K}_2$. Initially, both the keys are open and there is no charge on the capacitor. At an instant, key $\mathrm{K}_1$ is closed and immediately after this the current in $R_0$ is found to be $I_1$. After a long time, the current attains a steady state value $I_2$. Thereafter, $\mathrm{K}_2$ is closed and simultaneously $\mathrm{K}_1$ is opened and the voltage across $C_0$ oscillates with amplitude $V_0$ and angular frequency $\omega_0$.
Match the quantities mentioned in List-I with their values in List-II and choose the correct option.
| List-I | List-II |
|---|---|
| (P) The value of $I_1$ in Ampere is | (1) $0$ |
| (Q) The value of $I_2$ in Ampere is | (2) $2$ |
| (R) The value of $\omega_0$ in kilo-radians/s is | (3) $4$ |
| (S) The value of $V_0$ in Volt is | (4) $20$ |
| (5) $200$ |
| List - I | List - II |
|---|---|
| (P) $I_0$ in $\mathrm{mA}$ | (1) 44.4 |
| (Q) The quality factor of the circuit | (2) 18 |
| (R) The bandwidth of the circuit in $\mathrm{rad}~ \mathrm{s}^{-1}$ | (3) 400 |
| (S) The peak power dissipated at resonance in Watt | (4) 2250 |
| (5) 500 |
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STATEMENT 1
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Because
STATEMENT 2
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Numerical
The value of C is ____________.
The value of $$\varphi$$ is ____________.
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MCQ (More than One Correct Answer)
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$${V_Y} = {V_0}\,\sin $$ $$\left( {\omega t + {{2\pi } \over 3}} \right)$$
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