"BARC Subject Revision Quiz 6:Environmental Engineering+Engineering Mathematics''

An imholf tank combines which types of treatment process:

1) Sedimentation

2) Disposal

3) Digestion

4) Disinfection

What is the value of velocity gradient of a flocculation chamber 30 m long, 12 m wide and 5 m deep to treat 72 MLD of water having dynamic viscosity 1.29 × 10^–3 kg/m-sec and power input 1.2 kW.

Chlorine gas (8 mg/l) was added to a drinking water sample. If the free chlorine residual and pH was measured to be 2 mg/l and 7 .5 respectively, what is the concentration of residual OCl^- ions in the water? Assume that chlorine gas added to water is completely converted to HOCl and OCl^-. Atomic weight of Cl: 35 .5

Use: OCl^- + H⁺ HOCl; K = 10^7.5

A waste water plant produces 950 kg of dry solids per day at a moisture content of 92%. The solids are 60% volatile with a specific gravity of 1.1 and the remaining are non-volatile with a specific gravity of 2.54. What is the volume (in m³) of sludge after digestion, which reduces volatile solids content by 40% and decreases the moisture to 90%?

The value of particular integral (P.I.) of the differential equation  at , will be

The directional derivative of f = 2x² + 3y² + z² at the point P(2, 1, 3) in direction of the vector  is

The equation of the two lines of regression are, 2x + y + 5 = 0 and x + 2y + 7 = 0. The correlation co-efficient between ‘x’ and ‘y’ is

Find the area common to parabola y² = ax and the circle x² + y² = 4ax