Environmental Engineering in CE Noise produced by cooling fans (employed in air cooled heat exchangers or cooling tower) is mainly caused due to the turbulence created by blade passage through air. It can be reduced by use of a slower fan Both A & B With greater number of blades Of increased diameter Neither A nor B Both A & B With greater number of blades Of increased diameter Neither A nor B ANSWER DOWNLOAD EXAMIANS APP
Environmental Engineering in CE Replenishment of dissolved oxygen in water stream polluted with industrial waste occurs by Neither A nor B Natural aeration of water stream Both A & B Photosynthetic action of algae Neither A nor B Natural aeration of water stream Both A & B Photosynthetic action of algae ANSWER DOWNLOAD EXAMIANS APP
Environmental Engineering in CE The type of bacteria which is active in trickling filter during biological treatment of sewage is the __________ bacteria. Anaerobic Aerobic Saphrophytic Parasitic Anaerobic Aerobic Saphrophytic Parasitic ANSWER DOWNLOAD EXAMIANS APP
Environmental Engineering in CE BOD of raw municipal sewage may be in the range of about __________ mg/litre. 150-300 2000-3000 1-2 5-10 150-300 2000-3000 1-2 5-10 ANSWER DOWNLOAD EXAMIANS APP
Environmental Engineering in CE Maximum allowable concentration of CO₂ in air for safe working is __________ ppm (parts per million). 5000 50 1000 2000 5000 50 1000 2000 ANSWER DOWNLOAD EXAMIANS APP
Environmental Engineering in CE High noise level in a chemical plant can be controlled by the Suppression of noise at the source itself Path control of noise Protection of operating personnel All of these Suppression of noise at the source itself Path control of noise Protection of operating personnel All of these ANSWER DOWNLOAD EXAMIANS APP