A direct current of \(5~ A\) is superimposed on an alternating current \(I=10sin ~\omega t\) flowing through a wire. The effective value of the resulting current will be:

1.	\(15/2~A\)	2.	\(5 \sqrt{3}~A\)
3.	\(5 \sqrt{5}~A\)	4.	\(15~A\)

An ideal resistance R, ideal inductance L, ideal capacitance C, and AC voltmeters ${\mathrm{V}}_1,$ ${\mathrm{V}}_2,$ ${\mathrm{V}}_3$ $\mathrm{and}$ ${\mathrm{V}}_4$ are connected to an AC source as shown. At resonance:

In an L-C-R series AC circuit, the voltage across each of the components - L, C and R is 50 V. The voltage across the L-R combination will be:
1. 50 V
2. \(50 \sqrt{2} ~V\)
3. 100 V
4. 0 V 

An AC voltage source is connected to a series \(LCR\) circuit. When \(L\) is removed from the circuit, the phase difference between current and voltage is \(\frac{\pi}{3}\). If \(C\) is instead removed from the circuit, the phase difference is again \(\frac{\pi}{3}\) between current and voltage. The power factor of the circuit is:
1. \(0.5\)
2. \(1.0\)
3. \(-1.0\)
4. zero

An AC ammeter is used to measure the current in a circuit. When a given direct current passes through the circuit, the ac ammeter reads 6 A. When another alternating current passes through the circuit, the AC ammeter reads 8 A. Then the reading of this ammeter if DC and AC flow through the circuit simultaneously is:

1. $10\sqrt{2}$ A

2. 14 A

3. 10 A

4. 15 A

Calculate the Q-value of a series LCR circuit with L = 2.0 H, C = 32 μF and R = 10 \(\Omega\).

1. 35

2. 20

3. 15

4. 25

In the transformer shown in the figure, the ratio of the number of turns of the primary to the secondary is N₁/N₂=1/50. If a voltage source of 10 V is connected across the primary, then the induced current through the load of 10 kΩ in the secondary is:
        

1. \(\frac{1}{20}~A\)

2. zero

3. \(\frac{1}{10}~A\)

4. \(\frac{1}{5}~A\)

The variation of EMF with time for four types of generators is shown in the figures. Which amongst them can be called AC voltage?

(a)	(b)
(c)	(d)

The time required for a 50 Hz sinusoidal alternating current to change its value from zero to the r.m.s. value will be:

1. $1.5\times {10}^{-2}$ $\mathrm{s}$

2. $2.5\times {10}^{-3}$ $\mathrm{s}$

3. ${10}^{-1}$ $\mathrm{s}$

4. ${10}^{-6}$ $\mathrm{s}$

In a series RLC circuit, potential differences across R, L and C are 30 V, 60 V and 100 V respectively, as shown in the figure. The emf of the source (in volts) will be:

1. 190

2. 70

3. 50

4. 40