MCQOPTIONS
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MCQOPTIONS
This section includes 295 Mcqs, each offering curated multiple-choice questions to sharpen your Public Health Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 251. |
Coagulation is required when the particles are of |
| A. | fine |
| B. | coarse |
| Answer» B. coarse | |
| 252. |
The presence of calcium and magnesium bi-carbonates in water causes hardness in the water. |
| A. | Correct |
| B. | Incorrect |
| Answer» B. Incorrect | |
| 253. |
The most common coagulant is |
| A. | magnesium sulphate |
| B. | alum |
| C. | chlorine |
| D. | bleaching powder |
| Answer» C. chlorine | |
| 254. |
The maximum acidity in water will occur at a pH value of |
| A. | 0 |
| B. | 2 |
| C. | 7 |
| D. | 14 |
| Answer» B. 2 | |
| 255. |
Copper sulphate is the most common chemical used for controlling |
| A. | bacteria |
| B. | algae |
| C. | silt |
| D. | mineral matter |
| Answer» C. silt | |
| 256. |
The presence of carbon dioxide in water causes acidity. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 257. |
Suspended impurities cause turbidity in water. |
| A. | Yes |
| B. | No |
| Answer» B. No | |
| 258. |
In designing a water works for a city to meet the water demand for public use, a provision of about |
| A. | 5% |
| B. | 10% |
| C. | 20% |
| D. | 25% |
| Answer» C. 20% | |
| 259. |
Hard water may cause bursting of boilers. |
| A. | Agree |
| B. | Disagree |
| Answer» B. Disagree | |
| 260. |
In a rapid sand filter, the filter head varies from |
| A. | 1 to 1.5 m |
| B. | 1.5 to 2 m |
| C. | 2 to 4 m |
| D. | 4 to 5 m |
| Answer» D. 4 to 5 m | |
| 261. |
Rate of filteration of a slow sand filter ranges from |
| A. | 10 to 100 litres / h / m2 |
| B. | 100 to 200 litres / h / m2 |
| C. | 200 to 400 litres / h / m2 |
| D. | 400 to 1000 litres / h / m2 |
| Answer» C. 200 to 400 litres / h / m2 | |
| 262. |
Slow sand filter is more efficient for the removal of |
| A. | bacteria |
| B. | odour |
| C. | turbidity |
| D. | all of these |
| Answer» B. odour | |
| 263. |
The slow sand filter should be cleaned if the loss of head becomes more than |
| A. | 0.75 m |
| B. | 1.2 m |
| C. | 2.2 m |
| D. | 3.5 m |
| Answer» C. 2.2 m | |
| 264. |
After cleaning the slow sand filter, the filtered water should not be used for a period of |
| A. | upto 6 hours |
| B. | 6 hours to 12 hours |
| C. | 12 hours to 24 hours |
| D. | 24 hours to 48 hours |
| Answer» E. | |
| 265. |
The under drainage system in a rapid sand filters |
| A. | receives and collects the filtered water |
| B. | allows back washing for cleaning the filter |
| C. | both (a) and (b) |
| D. | none of these |
| Answer» D. none of these | |
| 266. |
Slow sand filter is efficient to remove the bacterias from the raw water to an extent of |
| A. | 50% |
| B. | 70% |
| C. | 85% |
| D. | 99% |
| Answer» E. | |
| 267. |
The coefficient of uniformity for slow sand filters is |
| A. | 1.35 |
| B. | 1.55 |
| C. | 1.75 |
| D. | 2.05 |
| Answer» D. 2.05 | |
| 268. |
The effective size of sand particles for slow sand filters varies from |
| A. | 0.30 to 0.35 mm |
| B. | 0.35 to 0.50 mm |
| C. | 0.50 to 0.65 mm |
| D. | 0.65 to 0.75 mm |
| Answer» B. 0.35 to 0.50 mm | |
| 269. |
Rapid sand filters are cheap and economical as compared to slow sand filters. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 270. |
The effective size of sand particles for rapid sand filters varies from |
| A. | 0.30 to 0.35 mm |
| B. | 0.35 to 0.50 mm |
| C. | 0.50 to 0.65 mm |
| D. | 0.65 to 0.75 mm |
| Answer» C. 0.50 to 0.65 mm | |
| 271. |
Water is forced at a preseure higher than the atmospheric pressure in rapid gravity filters. |
| A. | Right |
| B. | Wrong |
| Answer» C. | |
| 272. |
The coefficient of uniformity for rapid sand filters is |
| A. | more |
| B. | less |
| Answer» C. | |
| 273. |
Cleaning period for a slow sand filter is taken as |
| A. | 1 hour to 3 hours |
| B. | 1 day to 3 days |
| C. | 1 week to 3 weeks |
| D. | 1 month to 3 months |
| Answer» E. | |
| 274. |
Cleaning period for a rapid sand filter is taken as |
| A. | 2 to 3 hours |
| B. | 2 to 3 days |
| C. | 2 to 3 weeks |
| D. | 2 to 3 months |
| Answer» C. 2 to 3 weeks | |
| 275. |
To prevent the formation of crystalline hydrates of 'Ice' of chlorine, the chlorine supply cylinders are kept at a temperature from |
| A. | 10?C to 20?C |
| B. | 20?C to 27?C |
| C. | 27?C to 37?C |
| D. | 38?C to 42?C |
| Answer» E. | |
| 276. |
The portion of soil through which lateral movement of water takes place is called |
| A. | water tablean aquiclude |
| B. | an aquiclude |
| C. | zone of saturation |
| D. | none of these |
| Answer» D. none of these | |
| 277. |
Air vent pipe is not essentially required in a septic tank. |
| A. | True |
| B. | False |
| Answer» C. | |
| 278. |
The most commonly used chemical for dechlorination of water is |
| A. | sodium thiosulphate |
| B. | sodium sulphite |
| C. | potassium permaganate |
| D. | all of these |
| Answer» E. | |
| 279. |
The maximum permissible chlorine content for public supplies should be between |
| A. | 0.1 to 0.2 ppm |
| B. | 0.3 to 0.4 ppm |
| C. | 1.2 to 4 ppm |
| D. | 6.5 to 8 ppm |
| Answer» B. 0.3 to 0.4 ppm | |
| 280. |
The efficiency of sedimentation tank for a given discharge, can be increased by |
| A. | increasing the depth of tank |
| B. | decreasing the depth of tank |
| C. | increasing the surface area of tank |
| D. | decreasing the surface area of tank |
| Answer» D. decreasing the surface area of tank | |
| 281. |
Absolute pure water is good for health. |
| A. | Right |
| B. | Wrong |
| Answer» C. | |
| 282. |
The presence of calcium and magnesium chloride in water causes |
| A. | softening |
| B. | bad taste |
| C. | hardness |
| D. | turbidity |
| Answer» D. turbidity | |
| 283. |
The maximum permissible total solid content in water for domestic purposes should not exceed |
| A. | 300 ppm |
| B. | 400 ppm |
| C. | 500 ppm |
| D. | 1000 ppm |
| Answer» D. 1000 ppm | |
| 284. |
The most important source of water for public water supply is |
| A. | lake |
| B. | pond |
| C. | river |
| D. | sea |
| Answer» E. | |
| 285. |
Under steady low heads |
| A. | reciprocating |
| B. | centrifugal |
| Answer» C. | |
| 286. |
The discharge from washing places is called sullage. |
| A. | True |
| B. | False |
| Answer» B. False | |
| 287. |
A septic tank is a |
| A. | sedimentation tank |
| B. | digestion tank |
| C. | combination of sedimentation and digestion tank |
| D. | aeration tank |
| Answer» D. aeration tank | |
| 288. |
The sand, used for filteration, should not loose weight more than |
| A. | 2.50% |
| B. | 5% |
| C. | 7.50% |
| D. | 10% |
| Answer» C. 7.50% | |
| 289. |
When chlorine is added to raw water at more than one point, the process is termed as break point chlorination. |
| A. | Right |
| B. | Wrong |
| Answer» C. | |
| 290. |
Manholes on sewer lines are provided for |
| A. | periodic cleaning |
| B. | providing air for oxidation |
| C. | removal of part of sewerage |
| D. | all of these |
| Answer» B. providing air for oxidation | |
| 291. |
In the process of screening, the screens should be inclined at an angle of |
| A. | 10? to 20? |
| B. | 30? to 40? |
| C. | 45? to 60? |
| D. | 70? to 85? |
| Answer» D. 70? to 85? | |
| 292. |
The pocess of excluding large sized particles from water with the help of screens is called filteration. |
| A. | Yes |
| B. | No |
| Answer» C. | |
| 293. |
The length of rectangular sedimentation tank should not be more than |
| A. | twice |
| B. | three times |
| C. | four times |
| D. | six times |
| Answer» D. six times | |
| 294. |
Slow sand filter requires |
| A. | more |
| B. | less |
| Answer» B. less | |
| 295. |
Cleaning of rapid sand filters is done by |
| A. | scraping the top layer of filter media |
| B. | back washing |
| C. | providing new sand layers |
| D. | all of these |
| Answer» C. providing new sand layers | |