The major reason of hydrodynamic noise (i.e., noise resulting from liquid flow) is_________________?

Related Mcqs:

1. Aerodynamic noise resulting from turbulent gas flow is the most prevalent source of valve noise in fluid flow control. It is caused due to_________________?

   A. Reynold stresses
   B. Shear forces
   C. Both A. & B.
   D. Neither A. nor B.

2. Major sources of noise in furnace operation arises from air inspirators, combustion, side wall vibrations and fluctuation in the process heat load. A 50% increase in fuel firing rate may increase the furnace noise level by about ____________ decibels?

   A. 3
   B. 30
   C. 7
   D. 70

3. Noise pollution level in a chemical plant is expressed in __________________?

   A. Roentgen
   B. Decibel
   C. Hertz
   D. None of these

4. Noise level in a quiet private business office is about _____________ decibels?

   A. 25
   B. 50
   C. 70
   D. 85

5. Maximum allowable noise exposure limits for a man working for 8 hours a day in a noisy chemical plant is about ______________ decibels?

   A. 20
   B. 60
   C. 90
   D. 120

6. Maximum permissible limit of industrial noise as recommended by World Health Organisation (WHO) is _____________ decibels?

   A. 35
   B. 75
   C. 95
   D. 105

7. High noise level in a chemical plant can be controlled by the_________________?

   A. Suppression of noise at the source itself
   B. Path control of noise
   C. Protection of operating personnel
   D. All A., B. & C.

8. Noise level heard at a distance of about 100 metres from a jet engine with after burner is about _____________ decibels?

   A. 120
   B. 140
   C. 170
   D. 200

9. Noise level inside a jet airliner in normal flight is about ______________ decibels?

   A. 80
   B. 100
   C. 125
   D. 150

10. Noise emitted by a ventilation fan at a distance of 3 metres is about _____________ decibels?

    A. 85
    B. 105
    C. 125
    D. 145