Instrumentation and Process Control Mid - I, September - 2014

1.A capsule diaphragm is made by welding two diaphragms
  • To a solid base
  • Together at the centre
  • Together around the edge
  • To two other diaphragms
Answer: D
2.Which gauge measures pressure by sensing changes in the thermal conductivity of a gas?
  • Pirani gauge
  • Slack diaphragm gauge
  • McLeod gauge
  • None of them
Answer: C
3.A thermocouple gauge is one type of –
  • Ionization gauge
  • Thermal conductivity gauge
  • McLeod gauge
  • None of these
Answer: A
4.The full range from atmospheric pressure to a perfect vacuum is –
  • 14.7 psi
  • 0.40 torr
  • 7.14 psi
  • 0.01 – 0.40 torr
Answer: B
5.Diaphragms used in pressure applications are –
  • Light
  • Small in size
  • Slack
  • Bimetallic
Answer: A
6.A McLeod gauge can measure pressure as low as–
  • 0.05 torr
  • 0.005 torr
  • 0.0005 torr
  • 0.0005 torr
Answer: C
7.What are the basic pressure elements in a “mercury-less” manometer?
  • U-type
  • Syphons
  • Bellows or diaphragms
  • Capillary tubes
Answer: D
8.A capacitive pressure transducer indicates changes in pressure by changing the–
  • Voltage output of an ac circuit
  • Frequency
  • Capacitance
  • Alternating current
Answer: C
9.In case of variable head flowmeters, velocity of flowing liquid is –
  • Directly proportional to density of the flowing liquid
  • Inversely proportional to density of the flowing liquid
  • Inversely proportional to cross-sectional area of pipe through which fluid is flowing
  • None of the above.
Answer: C
10.Reynolds number–
  • Increases with increase in average velocity of liquid
  • Decreases with increase in absolute viscosity of liquid
  • Increases with increase in density of flowing liquid
  • All of the above.
Answer: B
11.In a segmental orifice plate, the diameter of the hole, which is a segment of a circle, is ____________________ of the pipe diameter.
Answer: 98%
12.Flow nozzles have very high coefficient of discharge, typically ___________________.
Answer: 0.99
13.The tube material of rotameter, commonly used ___________________.
Answer: Glass
14.In variable area flowmeters, the size of the restructure is adjusted by an amount to keep the ___________________ constant.
Answer: Pressure
15.Hot wire flow-meters measure the effect of the flowing fluid on a ________________
Answer: Hot body
16.A metering pump is a ___________________ pump.
Answer: +ve displacement
17.The mass flow-meters utilize the principle of ___________________.
Answer: Angular Momentum
18.A radiation pyrometer is sensitive to any ___________________ in the line of sight between it and the object.
Answer: Obstructions
19.The first step in a calibrating liquid in a glass thermometers is to determine their _________________ point.
Answer: Ice
20.A platinum resistance thermometer is used for temperature between -259°C and ___________________°C.
Answer: 630