A dual trace oscilloscope is set to operate in the Alternate mode. The control input of the multiplexer used in the y-circuit is fed with a signal having a frequency equal to
**A. ** the highest frequency that the multiplexer can operate properly

**B. ** twice the frequency of the time base (sweep) oscillator

**C. ** the frequency of the time base (sweep) oscillator

**D. ** haif the frequency of the time base (sweep) oscillator

**Answer : ****Option C**

**Explaination / Solution: **

No Explaination.

No Explaination.

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A band-limited signal with a maximum frequency of 5 kHz is to be sampled. According to the sampling theorem, the sampling frequency in kHz which is not valid is

**A. ** 5

**B. ** 12

**C. ** 15

**D. ** 20

**Answer : ****Option A**

**Explaination / Solution: **

No Explaination.

No Explaination.

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For linear time invariant systems, that are Bounded Input Bounded stable, which one of the following statement is TRUE?

**A. ** The impulse response will be integral, but may not be absolutely integrable.

**B. ** The unit impulse response will have finite support.

**C. ** The unit step response will be absolutely integrable.

**D. ** The unit step response will be bounded.

**Answer : ****Option B**

**Explaination / Solution: **

No Explaination.

No Explaination.

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Let f(x) be a real, periodic function satisfying f(−x) = −f(x). The general form of its Fourier series representation would be

**A. **

**B. **

**C. **

**D. **

**Answer : ****Option B**

**Explaination / Solution: **

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Given the finite length input x[n] and the corresponding finite length output y[n] of an LTI system as shown below, the impulse response h[n] of the system is

No Explaination.

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The frequency response of a linear, time-invariant system is given by The step response of the system is

**A. ** 5(1 - e^{-5t}) u(t)

**B. ** 5(1 - e^{-t/5}) u(t)

**C. ** 1/2 (1 - e^{-5t}) u(t)

**D. ** 1/5 (1 - e^{-t/5}) u(t)

**Answer : ****Option B**

**Explaination / Solution: **

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Let x(t) be the input and y(t) be the output of a continuous time system.

Match the system properties P1, P2 and P3 with system relations R1, R2, R3, R4

Properties Relations

P1 : Linear but NOT time - invariant R1 : y(t) = t^{2}x(t)

P2 : Time - invariant but NOT linear R2 : y(t) = t|x(t)|

P3 : Linear and time - invariant R3 : y(t) = |x(t)|

R4 : y(t) = x(t-5)

Mode function are not linear. Thus y(t) = |x(t)| is not linear but this functions is time invariant. Option (A) and (B) may be correct.

The y(t) = t|x(t)| is not linear, thus option (B) is wrong and (a) is correct. We
can see that

R1 : y(t) = t2x(t) Linear and time variant.

R2 : y(t) = t|x(t)| Non linear and time variant.

R3 : y(t) = |x(t)| Non linear and time invariant.

R4 : y(t) = x(t-5) Linear and time invariant.

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Let x(t) be a continuous time periodic signal with fundamental period T = 1 seconds. Let {a_{k}} be the complex Fourier series coefficients of x(t), where k is integer valued. Consider the following statements about x(3t):**A. ** only II and III are true

**B. ** only I and III are true

**C. ** only III is true

**D. ** only I is true

**Answer : ****Option B**

**Explaination / Solution: **

Fourier series coefficient ak is unaffected by scaling operating. Thus (I) is true and (II) is false.

I. The complex Fourier series coefficients of x(3t) are {a_{k}} where k is integer valued

II. The complex Fourier series coefficients of x(3t) are {3a_{k}} where k is integer valued

III. The fundamental angular frequency of x(3t) is 6𝜋 rad/s

For the three statements above, which one of the following is correct?

Fourier series coefficient ak is unaffected by scaling operating. Thus (I) is true and (II) is false.

T = 1sec for x(t) and if it compressed by '3' then the resultant period T = 1/3

Fundamental frequency = 2𝜋/T_{1= }= 6𝜋 rad/sec

Thus (III) is correct.

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A continuous-time function x(t) is periodic with period T. The function is sampled uniformly
with a sampling period T_{S}. In which one of the following cases is the sampled signal periodic?

**A. ** T = √2T_{s}

**B. ** T = 1.2Ts
**C. ** Always

**D. ** Never

**Answer : ****Option B**

**Explaination / Solution: **

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The input voltage given to a converter is

**A. ** 0.31

**B. ** 0.44

**C. ** 0.5

**D. ** 0.71

**Answer : ****Option C**

**Explaination / Solution: **

The current drawn by the converter is

The input power factor of the converter is

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**Preparation Study Material**- Circuit Analysis (Study/Preparation)
- Digital Electronics (Study/Preparation)
- Signals and Systems (Study/Preparation)
- Communication Theory (Study/Preparation)
- Basic Electrical and Instrumentation Engineering (Study/Preparation)
- Electrical Engineering and Instrumentation (Study/Preparation)
- Electronic Devices (Study/Preparation)
- Linear Integrated Circuits LIC (Study/Preparation)
- Electronic Circuits I (Study/Preparation)
- Electronic Circuits II (Study/Preparation)
- Control System Engineering (Study/Preparation)
- Digital Communication (Study/Preparation)
- Digital Signal Processing (Study/Preparation)
- Microprocessors and Microcontrollers (Study/Preparation)
- Electromagnetic Theory (Study/Preparation)