1141. Mercury is used in barometers because it :
A. Does not stick to the walls of the tubing
B. Is shining and can be read easily
C. Has practically zero vapour pressure
D. Has high density *
1142. The range of pressure for a particular bourdon tube is determined by the :
A. Graduations on the scale
B. Geometry of the mechanism
C. Strength of the return spring
D. Material and thickness of the tubing *
1143. The elastic element used for converting pressure to deformation in a conventional bourdon tube gauge is of___________cross section:
A. Circular
B. Elliptical *
C. Square
D. Rectangular
1144. Which of the following type of bourdon tube shape has a small tip travel and necessitates amplification ?
A. C-type *
B. Spiral
C. Helical
D. Twisted tube
1145. In a bourdon tube pressure gauge , incorrect readings may be encountered due to :
A. Hysteresis
B. Fatigue
C. Creep *
D. Drift
1146. The angular error in a bourdon tube refers to :
A. Pointer becomes loose on the spindle
B. Gauge tends to give a progressively higher or lower reading
C. Gauge reads correctly both at maximum and minimum *
D. Gauge reads correctly only at the mid point scale
1147. Most common material chosen for the fabrication of bellows pressure gauge is :
A. Leather
B. Plastic
C. Brass and Bronze *
D. Animal membrane
1148. Which of the followings cannot be used for the measureent of negative pressures ?
A. Piezometer tube *
B. Pirani gauge
C. Bourdon gauge
D. U-tube manometer
1149. All of the following devices are used for measuring vacuum, except :
A. Kenometer
B. Hydrometer *
C. Pirani gauge
D. Thermal Conductivity gauge
1150. Measurement of low pressure are made by sensing changes in the resistance of a heated filament exposed to that pressure. Which of the following gauges utilizes this principal ?
A. Ionisation gauge
B. Pirani-gauge *
C. Thermocouple vaccum gauge
D. Mcleod gauge