Practice Test: Question Set - 01
1. When a bare thermocouple is covered by a protective sheath, the response becomes
- (A) Faster
and oscillatory
- (B) Faster
and non-oscillatory
- (C) Slower
and oscillatory
- (D) Slower
and non-oscillatory
2. Which of the following thermocouples is incapable of measuring sub-zero (i.e., < 0°C) temperature?
- (A) Chromel-alumel
- (B) Iron-constantan
- (C) Platinum-platinum
+ rhodium
- (D) Copper-constantan
3. __________ temperature scale assigns 0° to the 'ice point' and 80° to the 'steam point'.
- (A) Celsius
- (B) Rankine
- (C) Reaumur
- (D) Fahrenheit
4. "An emf of the order of mV is generated when two solutions of different hydrogen ion concentration are separated by a thin glass wall". This is the working principle of a
- (A) pH
meter
- (B) Polarimeter
- (C) Chromatograph
- (D) Polarograph
5. The transfer function of a process is 1/(16s2 + 8s + 4). If a step change is introduced into the system, then the response will be
- (A) Under
damped
- (B) Critically
damped
- (C) Over
damped
- (D) None
of these
6. A control system has the following transfer function
F(s)
= [(s - 1)(s + 1)]/[s (s - 2)(s + 4)]
The initial value of the corresponding time function is
The initial value of the corresponding time function is
- (A) 1
- (B) 1/8
- (C) 7/8
- (D) -1
7. Bode diagram is a plot of
- (A) log (AR) vs.
log (f) and (φ) vs. log (f)
- (B) log (AR) vs. f and
log φ vs. f
- (C) AR vs.
log (f) and φ vs. log (f)
- (D) None
of these
8. Block diagram of a simple standard control system is shown below in the figure. Which of the following statement about the above control system is wrong?
- (A) The
transfer functions of the measuring element and the process is represent
by H and G2 respectively
- (B) The overall
transfer function for the change in load (X = 0) is given by Y/X1
= (Gc . G1 . G2)/(1 + Gc . G1 . G2
. H)
- (C) The overall
transfer function for the change in set point (X1 = 0)
is given by Y/X = (Gc . G1 . G2)/(1 + Gc . G1 . G2
. H)
- (D) Manipulated
variable is represented by C
9. A bolometer is
- (A) Used
for the measurement of thermal radiation
- (B) An
element which senses optical input and delivers thermal output
- (C) Both (a)
& (b)
- (D) Neither (a)
nor (b)
10. The frequency at which maximum amplitude ratio is attained is called the __________ frequency.
- (A) Corner
- (B) Resonant
- (C) Cross-over
- (D) Natural
11. The time constant of a first order process with resistance R and capacitance C is
- (A) R + C
- (B) R - C
- (C) RC
- (D) 1/RC
12. Thermocouple is suitable for measuring
- (A) Liquid
temperatures only
- (B) Very high
temperatures only
- (C) Very
low temperatures only
- (D) Both
high and low temperatures
13. Very low pressure is expressed in microns (μ), which is equal to __________ mm of Hg column (absolute) at 0°C.
- (A) 0.0001
- (B) 0.001
- (C) 0.01
- (D) 0.1
14. For the time domain function f(t) = t, the Laplace transform of ∫0t f(t) dt is given by
- (A) 1/2 S3
- (B) 2/S3
- (C) 1/S3
- (D) 2/S2
15. What is the overall transfer function (C/R) of the following block diagram if G = G1. G2. G3 and H = H1.H2.
- (A) 1/(1 + GH)
- (B) G/(1 + GH)
- (C) H/(1 + GH)
- (D) G/(1 - GH)