The output current versus time curve of a rectifier is shown in the figure. The average value of the output current in this case will be:

1.	0	2.	\(I_0 \over 2\)
3.	\(2I_0 \over \pi\)	4.	\(I_0\)

In the diagram, two sinusoidal voltages of the same frequency are shown. What is the frequency and the phase relationship between the voltages?
      

A coil of self-inductance L is connected in series with a bulb B and an AC source. The brightness of the bulb decreases when:

The variation of the instantaneous current (I) and the instantaneous emf (E) in a circuit are shown in the figure. Which of the following statements is correct?

In the circuit shown below, what will be the readings of the voltmeter and ammeter?
           

1. 800 V, 2 A

2. 300 V, 2 A

3. 220 V, 2.2 A

4. 100 V, 2 A

In an LCR circuit, the potential difference between the terminals of the inductance is 60 V, between the terminals of the capacitor is 30 V and that between the terminals of the resistance is 40 V. The supply voltage will be equal to:

1. 50 V

2. 70 V

3. 130 V

4. 10 V

An inductor of inductance L and resistor of resistance R are joined in series and connected by a source of frequency ω. The power dissipated in the circuit is:

1. $\frac{(R^2+{\omega }^2{L}^2)}{V}$

2. $\frac{V^{2}R}{(R^2+{\omega }^2{L}^2)}$

3. $\frac{V}{(R^2+{\omega }^2{L}^2)}$

4. $\frac{\sqrt{R^2+{\omega }^2{L}^2}}{V^2}$

In an ac circuit, a resistance of R ohm is connected in series with an inductance L. If the phase angle between voltage and current is 45°, the value of inductive reactance will be:

L, C and R represent physical quantities inductance, capacitance and resistance respectively. The combination representing the dimension of frequency will be:

1. LC

2. (LC)^–1/2

3. ${\left(\frac{{\displaystyle L}}{{\displaystyle C}}\right)}^{-1/2}$

4. $\frac{C}{L}$

An alternating current of frequency ‘f’ is flowing in a circuit containing a resistance R and a choke L in series. The impedance of this circuit will be:

1. R + 2πfL

2. $\sqrt{R^2+4{\pi }^2{f}^2{L}^2}$

3. $\sqrt{R^2+L^2}$

4. $\sqrt{R^2+2\pi fL}$