Transduction of Physical Variables Mid - II, November - 2014

1.The operation of a Pirani Gauge is based on
  • Ionization of Gas At Low Pressure
  • Variation of Volume With Pressure
  • Variation of Viscosity With Pressure
  • Variation of Thermal Conductivity of Gas With Pressure
Answer: D
2.In an Electromagnetic Flow Meter , the Induced Voltage generated is directly proportional to the
  • Flow Rate
  • Square root of the Flow Rate
  • Square of the Flow Rate
  • It is independent of Flow Rate
Answer: A
3.In a pitot static tube , the sources of error are
  • Misalignment
  • Effect of Viscosity
  • Two & Three Dimensional Velocity Flow
  • All of the above
Answer: D
4.Which of the following restrictions have highest discharge coefficient
  • Orifice Meter
  • Flow Nozzle
  • Venture Tube
  • Rotameter
Answer: C
5.Which of the following gauges can measure the lowest vaccum pressure
  • Mcleod Gauge
  • PiraniGauge
  • IonizationGauge
  • Knudson Gauge
Answer: C
6.For Gas Flows , ________________ serve as Tracers
  • Smoke
  • Helium – filled “soap” bubbles
  • Gas molecules made luminious
  • All of the above
Answer: D
7.Saturated Weston Cells remain Satisfactory as ______________ Standards for Periods of 10 to 20 years provided they are carefully treated.
  • Current
  • Frequency
  • Voltage
  • Capacitance
Answer: C
8.A body immersed in a flowing fluid is subjected to drag force Fd given by _____ where Cd is drag coefficient, A is area of cross section, ρis fluid mass density, v is velocity
  • Fd = (CdAρv2)/2
  • Fd = (Cd ) /2 Aρv2
  • 2 Aρv2/ (Cd )
  • None
Answer: A
9.Flow Nozzles are more _________ than Orifices but __________ than Venturis
  • Expensive, Cheaper
  • Expensive, Expensive
  • Cheaper, Expensive
  • Cheaper, Cheaper
Answer: A
10.Turbine Meters behave essentially as ___________ Order Dynamic Systems for small changes about an Operating Point
  • Zero
  • First
  • Second
  • None of the above
Answer: B
11.The Principle of __________________gauge is the compression of a sample of low pressure gas to a Pressure sufficiently high to read with simple manometer.
Answer: Mc-Leod
12.Kundsen gauge is insensitive to _____________________ .
Answer: Gas composition
13.In a Vortex Shedding Flow Meter, the shedding frequency ‘f’ is given by __________.
Answer: f = Nst.V/d
14.The output voltage of the microphone is generally ____________ and ______________ impedance level.
Answer: Small , High
15.Pirani Gauges are generally more __________________ than Thermocouple Gauges.
Answer: Accurate and Expensive
16.The range of a Knudsen gauge is ____________________ torr.
Answer: 10-8to 10-2
17.Yaw tubes are employed to determine the ____________________ of local flow velocity.
Answer: Direction
18.The sensitivity of an ionization gauge is given by S = ________________.
Answer: S = li/(P.le)
19.In a laser Doppler anemometer , the frequency of a particle moving across the dark and light fringe pattern with a velocity component ‘v’ normal to the fringes is given by f = ____________.
Answer: f =( 2v sin(/2))/
20.In electromagnetic flow meters the quantitative relation among variables is given by well known equation
Answer: E = BLv