# Environmental Engineering - Online Test

Q1. Match the given water properties in Group-I to the given titrants shown in Group-II Explaination / Solution:
No Explaination.

Q2. A 1 hour rainfall of 10 cm has return period of 50 year. The probability that 1 hour of rainfall 10 cm or more will occur in each of two successive years is
Explaination / Solution:

Return period of rainfall, T = 50 years
Probability of occurrence once in 50 years, p = 1/50 = 0.02
Probability of occurrence in each of 2 successive years  = p= (0.02)2 = 0.0004

Q3. An isohyet is a line joining points of
Explaination / Solution:
No Explaination.

Q4. In compacted cylindrical bituminous mix, VMA = 15%(void mineral aggregate); Vv = 4.5% (air void) The magnitude of VFB (void filled bituminous) is
Explaination / Solution:

VFB = VB/Vv = ((15-4.5)/15)×100% = 70%
Q5. Elevation and temperature data for places are tabulated below Based on this data, lapse rate can be referred as
Explaination / Solution:

Ambient lapse rate = ((21.25 - 15.70)/(444 - 4))×1000 = 12.6 oC/km[>9.8 oC/km]
When the ambient lapse rate exceeds the adiabatic lapse rate, the ambient lapse rate is said to be super adiabatic.

Q6. Storm-I of duration 5 hours gives a direct run-off of 4 cm and has an average intensity of 2cm / hr
Storm-II of 8 hour duration gives a run-off of 8.4 cm. (Assume φ -index is same for both the storms.)
The value of φ − index is
Explaination / Solution:

φ - index = (2×5-4)/5 = (10-4)/5 = 6/5 = 1.2 cm/hr

Q7. Storm-I of duration 5 hours gives a direct run-off of 4 cm and has an average intensity of 2cm / hr
Storm-II of 8 hour duration gives a run-off of 8.4 cm. (Assume φ -index is same for both the storms.)
Intensity of storm-II in cm/hr is
Explaination / Solution:

Let intensity of storm-II be P cm/hr 1.2 = (P×8-8.4)/8 ⇒ 1.2 × 8 +8.4 = P×8 ⇒ P = 2.25 cm/hr

Q8. The number of independent elastic constants for a linear elastic isotropic and homogeneous material is
Explaination / Solution:
No Explaination.

Q9. A coastal city produces municipal solid waste (MSW) with high moisture content, high organic materials, low calorific value and low inorganic materials. The most effective and sustainable option for MSW management in that city is
Explaination / Solution:
No Explaination.

Q10. According to the Noise Pollution (Regulation and Control) Rules, 2000, of the Ministry of Environment and Forests, India, the day time and night time noise level limits in ambient air for residential areas expressed in dB (A) Leq are
Explaination / Solution:
No Explaination.