Solution of Live Quiz Session for BARC ECE (held on 15th March) for ESE & GATE EC Exams

Question 1

The integral form of a Maxwell equation as given below, that depicts a time-varying magnetic field produces an electric field is popularly known as:

Question 2

With the initial values y(0)=y’(0)=1,the solution of the differential equation y’’+6y’+9y=6

at t=0 is

Question 3

Given below is a block diagram of an electric circuit.

The transfer function for the given system is obtained as:

Determine the value of

Question 4

A multi-range dc voltmeter is to be constructed by using individual multiplier resistors. A moving coil meter with internal resistance 80 Ω is to be used, which gives a full scale deflection with voltage 20 V. Determine the value of the multiplier resistors required, if the ranges of the voltmeter are 0 – 50 V, 0 – 100 V and 0 – 500 V.

Question 5

An air-core toroid has a cross-sectional area of 9 cm² and a mean radius of 16 cm. Calculate the magneto-motive force, if the flux produced is 1.7 µWb.

Question 6

A 10bit resistive divider is constructed such that the current through the LSB resistor is 100 μA. The maximum current that flow through the MSB resistor is ______ mA.

Question 7

For the non inverting amplifier circuit shown, find maximum operating frequency. The slew rate is 0.5V/ µs.

Question 8

A NBFM signal is converted into a WBFM signal using Armstrong method. The block diag is given below. The carrier freq. and the freq. devation at the output is

Question 9

A circular air-filled waveguide of radius 5cm is operated in the

mode. The waveguide is then completely filled with a dielectric of relative’s permittivity 2.25 and relative permeability 1.0. The cut-off wavelength for the

mode is 0.082m when the waveguide is filled with the dielectric, the cut off frequency will become nearby

Question 10

Which of the following are true regarding ROC:
i. If x (n) is a finite duration two – sided (non causal) signal, the ROC lies between z=0 and z= ∞.
ii. If X (z) is rational, then ROC includes all poles of X (z).
iii. If X (z) is rational, and if x (n) is two sided, then ROC is the region between two circles whose radius corresponds to the pole of the causal part with the largest magnitude and the pole of the anticausal part with smallest magnitude.
iv. If x (n) is infinite duration two – sided (non causal) signal, the ROC lies on the entire z – plane except the region between two circles of radius r1 and r2.