Environmental Engineering

Question: Inhalation of silica dust causes a disease called
[A].

bronchitis

[B].

silicosis

[C].

pneumoconiosis

[D].

none of these

Answer: Option B

Explanation:

No answer description available for this question.

Question: Average human body contains about __________ percent water by weight.
[A].

20

[B].

40

[C].

70

[D].

85

Answer: Option C

Explanation:

No answer description available for this question.

Question: Most of the bacteria in sewage are
[A].

parasitic

[B].

saprophytic

[C].

anerobic

[D].

none of these

Answer: Option B

Explanation:

No answer description available for this question.

Question: In sewage treatment, its sedimentation is speeded up by commonly adding
[A].

hydrochloric acid.

[B].

lime.

[C].

copper sulphate.

[D].

sodium sulphate.

Answer: Option B

Explanation:

No answer description available for this question.

Question: Aerodynamic noise resulting from turbulent gas flow is the most prevalent source of valve noise in fluid ilow control. It is caused due to
[A].

Reynold stresses

[B].

shear forces

[C].

both (a) & (b)

[D].

neither (a) nor (b)

Answer: Option C

Explanation:

No answer description available for this question.

Question: Noise produced by cooling fans (employed in air cooled heat exchangers or cooling tower) is mainly caused due to the turbulence created by blade passage through air. It can be reduced by use of a slower fan
[A].

with greater number of blades.

[B].

of increased diameter.

[C].

both (a) & (b).

[D].

neither (a) nor (b).

Answer: Option C

Explanation:

No answer description available for this question.

Question: 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].

70

[D].

100

Answer: Option A

Explanation:

No answer description available for this question.

Question: 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

Answer: Option C

Explanation:

No answer description available for this question.

Question: A man exposed to excessive noise level in the working environment may suffer from
[A].

hearing loss

[B].

rupture of ear drum

[C].

nervousness & fatigue

[D].

all (a), (b) & (c)

Answer: Option D

Explanation:

No answer description available for this question.

Question: Noise level during normal conversation among men is about __________ decibles.
[A].

10

[B].

45

[C].

90

[D].

115

Answer: Option B

Explanation:

No answer description available for this question.