Electronic Engineering MCQ Question Papers: ENTC, IT Interview Placement

Subject: Signals and Systems 4

**Part 4: List for questions and answers of Signals and Systems**

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**Q1. If a linear time invartant system is exicited by a pure random signal like white noise, the ****output of the linear system will have which of the following properties?**

**a) Output will be a white noise**

**b) Output will be periodic**

**c) Output will be random**

**d) Output will be correlated or coloured noise**

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**Q2. A signum function is**

**a) Zero for t greater than zero**

**b) Zero for t less than zero**

**c) Unity for t greater than zero**

**d) 2u****(t) – 1**

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**Q3. If a number of even functions are added, the resultant sum is**

**a) Even function**

**b) Odd funtion**

**c) Either even or odd function**

**d) Mixture of odd amd even functions**

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**Q4. The auto correlation of a sampling function is a**

**a) Triangular function**

**b) Gate function**

**c) Signum function**

**d) None of the above**

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**Q5. If a signal g(t) has energy E, then the energy of the signal g(2t) is equal to …**

**a) E/2**

**b) E/4**

**c) E**

**d) 2E**

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**Q6. FIR filter Passes __________ Phase**

**a) Non-linear phase**

**b) Linear phase**

**c) Variable phase**

**d) None **

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**Q7. A trigonometric series has**

**a) Single sided spectra**

**b) Zero**

**c) Sync function**

**d) Undefined**

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**Q8. If a number of odd functions are added, the resultant sum is**

**a) Even function**

**b) Odd funtion**

**c) Either even or odd function**

**d) Mixture of odd amd even functions**

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**Q9. In what range should Re(s) remains so that Laplace transform of the function e^(a + 2)t ****+ 5 exists?**

**a) Re(s) is greater than a + 2**

**b) Re(s) is greater than a + 7**

**c) Re(s) is less than a**

**d) Re(s) is greater than a + 5**

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**Q10. Which one of the following rules determines the mapping of s-plane to z-plane?**

**a) Right half of the s-plane maps into outside of the unit circle in z-plane**

**b) Left half of the s-plane maps into outside of the unit circle.**

**c) Imaginary axis in s-plane maps in to the circumference of the unit circle**

**d) All of the above**

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**Q11. F.T. of continuous non-periodic signal is**

**a) Aperiodic**

**b) Periodic**

**c) a and b**

**d) None**

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**Q12. Pick out the odd one**

**a) Stochastic variable**

**b) Stochastic function**

**c) Random variable**

**d) Random experiment **

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**Q13. Fourier transform of non periodic DT signal is**

**a) Aperiodic**

**b) Periodic**

**c) Both a and b**

**d) None of these**

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**Q14. State space analysis is applicable to**

**a) Time invariant systems**

**b) Time varying systems**

**c) Both time invariant and time varying systems**

**d) None of the above**

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**Q15. Fourier transform is defined for**

**a) Periodic**

**b) Non-periodic**

**c) Finite duration**

**d) All**

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**Q16. The derivative of unit step function is**

**a) Unit impulse**

**b) Ramp with slope 1**

**c) Impulse**

**d) Either (a) or (b)**

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**Q17. The coefficients Fn in the exponential form of Fourier series are**

**a) Independent of frequency**

**b) Functions of frequency**

**c) Even function of frequency**

**d) Odd functions of frequency**

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**Q18. The integral of k d(t) is**

**a) A step function of magnitude k**

**b) A step function ‘of magnitude 1/k**

**c) A ramp of slope k**

**d) A ramp of slope 1/k**

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**Q19. The integral of a unit impulse is**

**a) A unit step function**

**b) A ramp function of slope 1**

**c) A pulse function of magnitude 1**

**d) None of the above **

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**Q20. The units of the spectrum obtained be Fourier transforming the covariance function of ****a stationery Stochastic Process is**

**a) Power per Hz**

**b) Energy per Hz**

**c) Power per sec**

**d) Energy per second**

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**Part 4: List for questions and answers of Signals and Systems**

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**Q1. Answer: c**

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**Q2. Answer: d**

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**Q3. Answer: a**

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**Q4. Answer: b**

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**Q5. Answer: a**

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**Q6. Answer: a**

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**Q7. Answer: a**

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**Q8. Answer: b**

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**Q9. Answer: a**

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**Q10. Answer: d**

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**Q11. Answer: a**

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**Q12. Answer: d**

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**Q13. Answer: b**

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**Q14. Answer: c**

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**Q15. Answer: b**

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**Q16. Answer: a**

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**Q17. Answer: b**

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**Q18. Answer: a**

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**Q19. Answer: a**

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**Q20. Answer: b**