DAY 30 WORKSHEET LSGD (Water Quality and Sources )

The correct sequence of subsurface water movement from the surface to deep strata is —

• Percolation → Infiltration

• Infiltration → Percolation

• Absorption → Filtration

• Seepage → Absorption

Which of the following wells does not contain a strainer and draws water from a single water-bearing stratum?

• Strainer well

• Slotted well

• Cavity well

• Gravel-packed well

The size range of colloidal impurities present in water is —

• 10⁻¹ to 10⁻³ mm

• 10⁻³ to 10⁻⁶ mm

• 10⁻⁶ to 10⁻⁸ mm

• 10⁻⁸ to 10⁻¹⁰ mm

The average domestic water demand in an Indian city (GOI manual) lies in the range of —

• 100–150 lpcd

• 135–225 lpcd

• 200–300 lpcd

• 50–100 lpcd

The temperature limit for potable water beyond which it becomes unfit for drinking is —

• 20°C

• 26°C

• 35°C

• 40°C

TRUE OR FALSE

Contaminated water is always polluted, but polluted water may not be contaminated.

• True

• False

TRUE OR FALSE

Gravity springs yield water due to hydrostatic pressure between two impervious layers.

• True

• False

The chemical compound H₂O is called (a)   water.

The permissible temperature range for drinking water is ________ to ________ °C.

(a)  

The most common and widely used tube well type in India is the (a)   well.