# Online Electronics and Communication Engineering Test - Networks Analysis and Synthesis Test 3 Loading Test...

Instruction:

• This is a FREE online test. DO NOT pay money to anyone to attend this test.
• Total number of questions : 20.
• Time alloted : 30 minutes.
• Each question carry 1 mark, no negative marks.
• DO NOT refresh the page.
• All the best :-).

1.

A network has two branches in parallel. One branch contains impedance Z1 and the other branch has impedance Z2. If it is fed from an ac voltage V of frequency f, the current through Z1 depends, on

A.
 V, Z1, Z2 B.
 V, Z1 C.
 Z1, Z2 D.
 V, Z1, f Explanation:

In parallel branches, the current through any branch depends only on voltage, impedance and frequency only.

2.

In figure the voltage drop across the 10 Ω resistance is 10 V. The resistance R A.
 is 6 Ω B.
 is 8 Ω C.
 is 4 Ω D.
 cannot be found Explanation:

Current supplied by battery = Therefore current through 2Ω resistance is 11 A. Voltage across R = 48 - 10 - 11 x 2 = 16 V.

3.

Two similar coils have self inductance of 1 mH each. Coefficient of coupling is 0.5. The mutual inductance M is

A.
 0.25 mH B.
 0.5 mH C.
 0.707 mH D.
 1 mH Explanation:

M = kL1L2

4.

The rms voltage measured across each of the circuit element in figure is as shown, when the circuit is excited by a sinusoidal voltage Es, the rms value of the source voltage es is A.
 10 volt B.
 2 volt C.
 Es D.
 5 volt Explanation:

Voltage across C = -10jv

Voltage across L = + 14 jv

source voltage Es = VR + jVL - jVC = 3 + j. 14 - j. 10 3 + j4

rms of Es = VR2(VL - VC)2 = 32 + 42 5 volt.

5.

The ABCD parameters of ideal n : 1 transformer shown in the figure are . The value of X will be A.
 n B.
 1/n C.
 n2 D.
 1/n2 Explanation:  .

6.

In figure V is ideal voltmeter having infinite resistance. It will read __________ volt. A.
 40 B.
 60 C.
 0 D.
 100 Explanation: 7.

The correct relation between joules and calories is

A.
 calories = joules/4.156 B.
 joules = calories/4.156 C.
 calories = joules x 107/4.156 D.
 joules = calories x 107/4.156 Explanation:

Calories and joules are related by J, i.e., mechanical equivalent of heat.

8.

A certain network has two ideal voltages sources and a large number of ideal resistances. The power consumed in one of the resistances is 4 W when either of two sources is active and the other source is active and the other source is short circuited. When both sources is short circuited.When both sources are active, the power consumed in the same resistor would be

A.
 zero or 16 W B.
 4 W or 8 W C.
 zero or 8 W D.
 8 W or 16 W Explanation:

If currents of both sources add, total current would be twice and power is four time, i.e., 16 W. If currents subtract, net current and power are zero.

9.

Assertion (A): The impedance of a series resonant circuit is minimum at resonance.

Reason (R): Resonance condition implies unity power factor condition.

A.
 Both A and R are true and R is correct explanation of A B.
 Both A and R are true and R is not the correct explanation of A C.
 A is true but R is false D.
 A is false but R is true Explanation:

Since power factor is unity, impedance is minimum.

10.

The following circuit resonates at A.
 0.5 Hz B.
 5 Hz C.
 1 rad/sec D.
 0.5 rad/sec 11.

A steel bar needs 1200 AT to magnetise it. The voltage that must be applied to the magnetising coil of 100 turns and 10 Ω resistance is __________ volt.

A.
 120 B.
 12 C.
 1200 D.
 10 12.

Poor power factor

A.
 reduces load handling capability of electrical system B.
 results in more power losses in the electrical system C.
 overloads alternators, transformers and distribution lines D.
 all 13.

A reactance function is always a quotient of

A.
 even to odd polynomials B.
 odd to even polynomials C.
 even to odd or odd to even polynomials D.
 even to even polynomials 14.

The Z parameter of the following T-network is A.  B.  C.  D.
 not possible 15.

In figure the effective resistance faced by voltage source is A.
 1 Ω B.
 2 Ω C.
 3 Ω D.
 3.3 Ω 16.

Which of the following statements is incorrect?

A.
 A mesh with two resistors has two mesh currents B.
 The algebraic sum of all voltages around any mesh or any loop must be zero C.
 The principle node is a function where branch current can divide or combine D.
 A Norton is a series circuit 17.

In ZRC (s) = constant at s = 0, the last element in first Foster cauer realization is

A.
 R B.
 C C.
 R and C in series D.
 R and C in parallel 18.

For a series circuit of R and variable XL the admittance locus is

A.
 a semicircle in first quadrant B.
 a semicircle in fourth quadrant C.
 a straight line in first quadrant D.
 a straight line in fourth quadrant 19.

Assertion (A): In drawing an electric circuit analogous to a mechanical circuit, spring is replaced by capacitance.

Reason (R): The behaviour of a spring and capacitor are similar.

A.
 Both A and R are true and R is correct explanation of A B.
 Both A and R are true and R is not the correct explanation of A C.
 A is true but R is false D.
 A is false but R is true 20.

Norton's equivalent circuit

A.
 is same as Thevenin's circuit B.
 has no relation with Thevenin's circuit C.
 is dual of Thevenin's circuit D.
 is reciprocal of Thevenin's circuit 