Prepare for UPSC Indian Engineering Services (IES/ESE) with official previous years' questions, detailed derivations, phasor analysis, and circuit solutions across Electrical Machines, Power Systems, Control Systems, Power Electronics, Network Theory, and Analog & Digital Circuits.
Marking pattern: +2.00 positive, -0.66 negative (Official UPSC ESE 1/3rd Negative Marking Scheme; 150 Questions, 300 Marks).
Consider the following characteristics regarding an ideal operational amplifier:
Which of the above characteristics is/are correct?
An inverting amplifier using the 741C must have a flat response up to 40 kHz. The gain of the amplifier is 10. What maximum peak-to-peak input signal can be applied without distorting the output?
Consider the following statements regarding bistable multivibrator:
Which of the above statements is/are correct?
What is the percentage of resolution of the eight-bit DAC?
What is the value of the capacitance to use in a capacitor filter connected to a full-wave rectifier operating at a standard aircraft power frequency of 400 Hz, if the ripple factor is 10% for a load of 500 Ω?
Match the following Lists regarding R-C filter circuit:
| List-I [Component] | List-II [Output voltage (V_{out})] |
|---|---|
| P. Low-pass filter | 1. $$\frac{1}{RC}\int_{0}^{t}V_{in}dt$$ |
| Q. R-C circuit as integrator | 2. $$V_{in}\frac{\omega RC}{\sqrt{1+(\omega RC)^2}}$$ |
| R. High-pass filter | 3. $$RC\frac{dV_{in}}{dt}$$ |
| S. R-C circuit as differentiator | 4. $$V_{in}\frac{1}{\sqrt{1+(\omega RC)^2}}$$ |
Select the correct answer using the code given below:
Match the following Lists:
| List-I (Name of the flag) | List-II (Bit position in flag register) |
|---|---|
| P. Auxiliary carry flag | 1. $$D_0$$ |
| Q. Parity flag | 2. $$D_2$$ |
| R. Zero flag | 3. $$D_4$$ |
| S. Carry flag | 4. $$D_6$$ |
Select the correct answer using the code given below:
Match the following Lists regarding interfacing the 8155 memory section:
| List-I (Address lines) | List-II (Function used for) |
|---|---|
| P. $$A_{11}\text{ to }A_{15}$$ | 1. Don't Care |
| Q. $$A_0\text{ to }A_7$$ | 2. Chip Enable |
| R. $$A_8\text{ to }A_{10}$$ | 3. Register Select |
Select the correct answer using the code given below:
The emission current of a diode is 12.5 mA. What is the rms value of shot noise current for a 10 MHz bandwidth?
A transmitter supplies 10 kW power to an aerial, when unmodulated. What is the power radiated, when modulated to 30%?
Consider the following statements regarding AM versus FM broadcasting:
Which of the above statements is/are correct?
The signal voltage and noise voltage of a system are 0-923 mV and 0-267 mV respectively. What is the signal-to-noise ratio (SNR) in number?
Match the following Lists regarding sampling techniques:
| List-I (Sampling technique) | List-II (Principle) |
|---|---|
| P. Natural sampling | 1. It uses sample-hold principle |
| Q. Flat-top sampling | 2. It uses multiplication |
| R. Ideal sampling | 3. It uses multiplication or chopping principle |
Select the correct answer using the code given below:
The diode falls under which type of system?
Which of the following properties of convolution system exhibits/exhibit the result of superposition principle for unit impulse response in linear time-invariant systems?
The signal space should be divided as
Consider a non-recursive filter with the impulse response $$h(n)$$ shown in the figure below:
What is the group delay in terms of frequency?
If $$h(t) = \left[-\frac{2}{3}e^{t} + \frac{2}{3}e^{-2t}\right]u(-t) + \delta(t)$$, then the function is
The unit impulse response of an LTI system is $$h(t) = e^{-t}\sin(2t)u(t)$$. What is the response to $$x(t) = \sin(t)$$ by using the Laplace transform?
If $$x(n) = \{..., 0, 0, 1, 1, 1, 1, 1, 1, 0, 0, ...\}$$ with the first '1' located at $$n = 0$$, what is the value of $$y(n) = x(2n)$$?
Consider a finite-duration sequence such as $$x(n) = \{1, 2, 4, 8, 16\}$$. What is the new sequence produced, when it revolves 4 units in the circular shift operation?
What is the linear convolution response $$y(5)$$ of the given sequence?
$$x(n)=\begin{cases}\frac{2}{\sqrt{3}}\sin\left(\frac{\pi n}{3}\right), & 0\le n\le 5 \\ 0 & \text{elsewhere}\end{cases}$$
and $$h(n)=\{1, 2, 3, 2, 1\}$$
By using the 3-point DFT of the sequence $$h(n)=a^{-n}$$, $$0\le n\le 2$$, for $$a=1.369$$, what is the relationship between the output sequences?
If $$X(s)=\mathcal{L}\{x(t)\}$$, what is the initial value $$x(0)$$ and the final value $$x(\infty)$$ respectively, for the given signal $$X(s)=\frac{7s+6}{s(3s+5)}$$ using initial value and final value theorems?
If $$X(s)=\mathcal{L}\{x(t)\}$$, what is the inverse Laplace transform of the signal $$X(s)=\frac{2}{s(s+1)(s+2)^2}$$?