Related Mcqs:

1. 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

2. Nitrogen gas constant volume thermometer is suitable for measuring a temperature of _____________ °C?

   A. 0-100
   B. < 0
   C. > 100
   D. > 50

3. A constant volume gas thermometer employing ______________ is used to measure sub-zero (i.e., < 0°C) temperature?

   A. Helium
   B. Hydrogen
   C. Nitrogen
   D. None of these

4. Helium gas constant volume thermometer is suitable for the measurement of a temperature of ______________ °C?

   A. < 100
   B. < 0
   C. > 0
   D. > 800

5. The unit of ‘time constant’ of a system is the same as that of___________________?

   A. Velocity
   B. Time
   C. (Time)-1
   D. None of these

6. Resistance of a gas in a vessel is given by (where, P = pressure, V = volume of the vessel, n = no. of moles of the gas, R = gas constant) ?

   A. V/nRT
   B. nRT/V
   C. nRT/P
   D. P/nRT

7. Sub-zero temperature (< 0°C) can be measured by a constant volume gas thermometer employing ?

   A. Helium
   B. Nitrogen
   C. Hydrogen
   D. None of these

8. 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°

9. 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______________?

   A. 1
   B. 0.5
   C. 1/√2
   D. 0.25

10. 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