Environmental Engineering

Question: Noise level heard inside a bus in busy city traffic or inside a sub-way train corresponds to about __________ decibels.
[A].

75

[B].

95

[C].

120

[D].

140

Answer: Option B

Explanation:

No answer description available for this question.

Question: Noise level audible to audience sitting in the 5th row from the stage during a large orchestra show corresponds to about __________ decibels.
[A].

105

[B].

135

[C].

160

[D].

185

Answer: Option B

Explanation:

No answer description available for this question.

Question: Noise emitted by a ventilation fan at a distance of 3 metres is about __________ decibels.
[A].

85

[B].

105

[C].

125

[D].

145

Answer: Option B

Explanation:

No answer description available for this question.

Question: The biological decomposition of organic substances in wastes controlled conditions is called
[A].

incineration

[B].

biological oxidation

[C].

composting

[D].

none of these

Answer: Option C

Explanation:

No answer description available for this question.

Question: Fine grit present in sewage is removed in the __________ during sewage treatment.
[A].

grit chamber

[B].

detritus tank

[C].

trickling filter

[D].

skimming tank.

Answer: Option B

Explanation:

No answer description available for this question.

Question: In sewage treatment, the detention period allowed for oxidation ponds ranges from __________ weeks.
[A].

1 to 2

[B].

4 to 5

[C].

9 to 10

[D].

15 to 20

Answer: Option B

Explanation:

No answer description available for this question.

Question: A shallow pond in which the sewage is retained and biologically treated is called
[A].

oxidation

[B].

Imhoff tank

[C].

lagoon

[D].

skimming tank

Answer: Option A

Explanation:

No answer description available for this question.

Question: During sewage treatment, the sewage is subjected to __________ treatment in Imhoff tank.
[A].

filtration

[B].

digestion

[C].

sedimentation

[D].

both (b) and (c)

Answer: Option D

Explanation:

No answer description available for this question.

Question: __________ substances present in sewage are removed in grit chamber during sewage treatment.
[A].

Organic

[B].

Fatty

[C].

Inorganic

[D].

Dissolved

Answer: Option C

Explanation:

No answer description available for this question.

Question: Fresh sewage is __________ in nature.
[A].

acidic

[B].

neutral

[C].

alkaline

[D].

highly acidic

Answer: Option C

Explanation:

No answer description available for this question.