A first order system with unity gain and time constant η is subjected to a sinusoidal input of frequency w = 1/η. The amplitude ratio for this system is______________?

Related Mcqs:

1. What is the ratio of output amplitude to input amplitude for a sinusoidal forcing function in a first order system ?

   A. 1
   B. > 1
   C. < 1
   D. None of these

2. A first order system with a time constant of 1 min is subjected to frequency response analysis. At an input frequency of 1 radian/min, the phase shift is______________?

   A. 45°
   B. -90°
   C. -180°
   D. -45°

3. According to Bode stability criterion, a system is unstable, if the open loop frequency response exhibits an amplitude ratio exceeding unity at frequency for which phase lag is_________________?

   A. 0°
   B. 45°
   C. 90°
   D. 180°

4. “A control system is unstable, if the open loop frequency response exhibits an amplitude ratio exceeding unity at the crossover frequency.” This is _______________ criterion?

   A. Bode stability
   B. Nyquist
   C. Routh stability
   D. None of these

5. The time constant of a unity gain, first order plus time delay process is 5 min. If the phase lag at a frequency of 0.2 rad/min is 60°, then the dead time (in minutes) is________________?

   A. 5π/12
   B. π/6
   C. π/12
   D. π/3

6. Suppose that the gain, time constant and dead time of a process with the following transfer function: Gc(s) = 10 exp( – 0.1s)/(0.5s + 1) are known with a possible error of ± 20% of their values. The largest permissible gain Kc of a proportional controller needs to be calculated below taking the values of process gain, time constant and dead time as________________?

   A. 8, 0.6, 0.08
   B. 12, 0.6, 0.12
   C. 8, 0.6, 0.12
   D. 12, 0.4, 0.08

7. The frequency at which maximum amplitude ratio is attained is called the ______________ frequency?

   A. Corner
   B. Resonant
   C. Cross-over
   D. Natural

8. The amplitude ratio for the sinusoidal response of __________ is < 1?

   A. Transportation lag
   B. First order system
   C. Second order system
   D. None of these

9. The amplitude ratio for the sinusoidal response of a _____________ is 1?

   A. First order system
   B. Second order system
   C. Transportation lag
   D. None of these

10. Phase lag of the frequency response of a second order system to a sinusoidal forcing function______________?

    A. Is 30°
    B. Is 90° at the most
    C. Approaches 180° asymptotically
    D. Is 120°