Pollution by particulate matter emission in the atmosphere does not take place during metal Cutting Machining Grinding Polishing TRUE ANSWER : ? YOUR ANSWER : ?
Fluorosis (a bone disease) is caused by the presence of high concentration of __________ in atmospheric air. Hydrogen sulphides Hydrogen flouride Nitrogen dioxide Hydrocarbons TRUE ANSWER : ? YOUR ANSWER : ?
BOD of raw municipal sewage may be in the range of about __________ mg/litre. 2000-3000 150-300 1-2 5-10 TRUE ANSWER : ? YOUR ANSWER : ?
Which is the most practical and economical method for removal of suspended solid matter from polluted water? Biological oxidation Sedimentation Chlorination Skimming off TRUE ANSWER : ? YOUR ANSWER : ?
Which of the following radioactive wastes emits all α, β & γ rays and hence is the most hazardous of all radioactive emitters? Au-198 I-131 Ra-226 Sr-90 TRUE ANSWER : ? YOUR ANSWER : ?
A man exposed to excessive noise level in the working environment may suffer from All of these Hearing loss Nervousness & fatigue Rupture of ear drum TRUE ANSWER : ? YOUR ANSWER : ?
The widest explosive limit is of __________ , thereby making it the most explosive gas. Acetylene Hydrogen Carbon monoxide Petrol vapor TRUE ANSWER : ? YOUR ANSWER : ?
Noise level heard at a distance of about 100 metres from a jet engine with after burner is about __________ decibels. 200 120 170 140 TRUE ANSWER : ? YOUR ANSWER : ?
Iron & manganese present as pollutant in water can not be removed by Chlorination Lime soda process or manganese zeolite process Oxidation followed by settling & filtration Ion exchange process TRUE ANSWER : ? YOUR ANSWER : ?
Presence of nitrates in water in excess of 50 ppm causes Gastroentetitis Tooth decay Asphyxiation Mathenoglobenemia TRUE ANSWER : ? YOUR ANSWER : ?