Practice Pakistan's most useful MCQs for competitive exams

Liquid column manometers are used for measuring the pressure ______________ kgf/cm2?

• (A)  > 2 (gage)
• (B)  < 3 (gage)
• (C)  < 10 (gage)
• (D)  < atmospheric

Answer

Submitted By :Ali Uppal

Continuous measurement of moisture content of paper in paper industry is done by measuring the_________________?

• (A)  Thermal conductivity through the paper
• (B)  Electrical resistance through the paper
• (C)  Magnetic susceptibility
• (D)  None of these

Answer

Submitted By :Ali Uppal

Mcleod gauge measures the _____________ pressure?

• (A)  Positive
• (B)  Sub-atmospheric
• (C)  Very high
• (D)  Atmospheric

Answer

Submitted By :Ali Uppal

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°

Answer

Submitted By :Ali Uppal

All the thermocouples used for temperature measurement use dissimilar metal ________________?

• (A)  Strips
• (B)  Bars
• (C)  Wires
• (D)  Beads

Answer

Submitted By :Ali Uppal

Dead zone is the__________________?

• (A)  Same as time constant
• (B)  Same as transportation lag
• (C)  Maximum change in the variable that does not change the reading of the instrument
• (D)  None of these

Answer

Submitted By :Ali Uppal

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

Answer

Submitted By :Ali Uppal

The transfer function for a P-D controller is________________?

• (A)  Kc(1+ηD s)
• (B)  Kc(1 +1/ηD s)
• (C)  Kc η
• (D)  s

Answer

Submitted By :Ali Uppal

Water is entering a storage tank at a temperature T0 and flow rate Q0 and leaving at a flow rate Q and temperature T. There are negligible heat losses in the tank. The area of cross-section of the tank is A0. The model that describes the dynamic variation of temperature of water in the tank with time is given as________________?

• (A)  Q0(T0 – T) = Ac . h (dT/dt)
• (B)  Q0T0 – QT = Ac . h (dT/dt)
• (C)  Q(T0 – T) = Ac . h (dT/dt)
• (D)  Q(T0 – T) = Ac . (dTH/dt)

Answer

Submitted By :Ali Uppal

The root locus plot of the roots of the characteristics equation of a closed loop system having the open loop transfer function K (s + 1)/[2 (2s + 1) (3s + 1)] will have a definite number of loci for variation of K from 0 to ∞. The number of loci is_______________?

• (A)  1
• (B)  2
• (C)  3
• (D)  4

Answer

Submitted By :Ali Uppal