In an AC circuit, the current is given by; $i=5\sin\left(100t-\frac{\pi}{2}\right)$ and the AC potential is $V =200\sin(100 t)~\text V.$ The power consumption is:
1. $20~\text W$
2. $40~\text W$
3. $1000~\text W$
4. zero

In an $LCR$ circuit having $L = 8.0~\text{H}$, $C= 0.5~\mu\text{F}$ and $R = 100~\Omega$ in series, what is the resonance frequency?
1. $600$ radian/sec
2. $600$ Hz
3. $500$ radian/sec
4. $500$ Hz

A circuit consists of $3$ ohms of resistance and $4$ ohms of reactance. The power factor of the circuit is:

The power factor of a good choke coil is:

1. Nearly zero

2. Exactly zero

3. Nearly one

4. Exactly one

The phase difference between the current and voltage of LCR circuit in series combination at resonance is 

(1) 0

(2) π/2

(3) π

(4) –π

In a series $LCR$ circuit, resistance $R=10~\Omega$ and the impedance $Z=20~\Omega$. The phase difference between the current and the voltage will be:
1. $30^{\circ}$
2. $45^{\circ}$
3. $60^{\circ}$
4. $90^{\circ}$

The power factor of an ac circuit having resistance (R) and inductance (L) connected in series and an angular velocity ω is 

(1) $R/\omega L$

(2) $R/{(R^2+{\omega }^2{L}^2)}^{1/2}$

(3) $\omega L/R$

(4) $R/{(R^2-{\omega }^2{L}^2)}^{1/2}$

In an LR-circuit, the inductive reactance is equal to the resistance R of the circuit. An e.m.f. $E=E_0\cos \left(\omega t\right)$ applied to the circuit. The power consumed in the circuit is:

(1) $\frac{E_0^2}{R}$

(2) $\frac{E_0^2}{2R}$

(3) $\frac{E_0^2}{4R}$

(4) $\frac{E_0^2}{8R}$

In the circuit shown in the figure, neglecting source resistance, the voltmeter and ammeter reading respectively will be:

1. $0~\text{V}, 3~\text{A}$
2. $150~\text{V}, 3~\text{A}$
3. $150~\text{V}, 6~\text{A}$
4. $0~\text{V}, 8~\text{A}$