Instrumentation and Control MCQs

Question 1

Local velocity is measured by a:

Accepted Answer

Pitot tube

Answer

Venturi tube

Answer

Orifice plate

Answer

(a) vena contracta device

Question 2

Flange taps in case of orifice plate are installed:

Accepted Answer

25 mm from each side of the orfice plate

Answer

D (pipe diameter) upstream and D/2 downstream

Answer

Just at surface of orifice plate

Answer

2.5 D upstream and 8 D downstream

Question 3

Vena-contracta taps are employed :

Accepted Answer

D upstream and at vena contracta

Answer

D upstream and D downstream from the plate

Answer

2 D upstream and at vena contracta

Answer

Just at surface of plate upstream and at vena contracta

Question 4

For an orfice plate having ratio of inside and pipe diameter as 0.5, the pressure loss in comparison to differential pressure created is of the order of :

Accepted Answer

50%.

Answer

-0.05

Answer

0.2

Answer

0.35

Question 5

15? taper venturi tube causes loss of following % of the differential pressure :

Accepted Answer

0.1

Answer

0.05

Answer

0.2

Answer

0.3

Question 6

Pick out false statement about advantages of orifice plates, used for flow measurement:

Accepted Answer

Highturn-down ratio

Answer

No moving parts

Answer

Long-term reliability

Answer

Inexpensive

Question 7

Pick out false statement about disadvantages of orifice plates :

Accepted Answer

Short-term reliability

Answer

Square root relationship

Answer

Poor turn-down ratio

Answer

Critical installation requirements

Question 8

Dall tube is another variation of

Accepted Answer

Venturi tube

Answer

Orifice plate

Answer

Nozzle

Answer

Rotameter

Question 9

Target meter is concerned with measurement of :

Accepted Answer

Flow

Answer

Pressure

Answer

Viscosity

Answer

Density