NCERT SOLUTIONS : MANUFACTURING INDUSTRIES

NCERT SOLUTIONS : MANUFACTURING INDUSTRIES

Q.2: Answer the following in brief: 

(i) What is manufacturing?
Solution: (i) Production of goods in large quantities after processing from raw materials to ready-to-use, more valuable products is called Manufacturing.
(ii) Name any three physical factors for the location of the industry. 
(ii) 1. Availability of raw material. 2. Suitable climate. 3. Availability of water and power supply. 4. Transport facilities.
(iii) Name any three human factors for the location of an industry. 
(Any three) (iii) 1- Labour. 2- Market. 3- Government policies.
(iv) Name the important raw materials used in manufacturing of cement.
 (iv) Raw materials used in manufacturing of cement are – limestone, silica, alumina, gypsum.
 Q.3: Answer the following questions in about 120 words: 
(i) How are integrated steel plants different from mini steel plants? What problems does the industry face? What recent developments have led to a rise in the production capacity? 
Solution: (i) Integrated Steel Plants are large plants which handle everything in one complex – from putting together raw material to steel making, rolling and shaping. Mini Steel Plants are smaller, have electric arc furnaces, use mainly steel scrap and sponge iron as inputs. They have re-rollers that use steel ingots as well. They produce mild and alloy steel of given specifications. Problems of Steel Industry a. High costs and limited availability of coking coal. b. Lower productivity of labour. c. Irregular supply of power. d. Poor infrastructure. Following are some recent developments that have led to a rise in the production capacity – a. Liberalisation b. Foreign direct investments (FDI) with the efforts of private entrepreneurs. c. Improvement in production process by the use of newer technologies.
(ii) How do industries pollute environment? 
ii) Industries are responsible for four types of pollution – air, water, land, and noise pollution. Following are the various reasons: 1. Air pollution is caused by the presence of high proportion of undesirable gases, such as sulphur dioxide and carbon monoxide. 2. Water pollution is caused by organic and inorganic industrial wastes and effluents discharged into rivers. 3. Thermal pollution of water occurs when hot water from factories and thermal plants are drained into rivers and ponds before cooling. 4. Wastes from nuclear plants cause cancer, birth defects and miscarriages. 5. Dumping of wastes especially, glass, harmful chemicals, industrial effluents, packaging, salts and other garbage render the soil useless. 6. Noise pollution is caused due to industrial and construction activities, factory equipment, generators, electric saws, drills and other machineries.
(iii) Discuss the steps to be taken to minimize environmental degradation by industry.
(iii) The steps to be taken to minimize environmental degradation by industry are: 
Minimizing water pollution: 1. Minimizing use water for processing by reusing and recycling it in two or more successive stages. 2. Harvesting of rainwater to meet water requirements. 3. Treating hot water and effluents before releasing them in rivers and ponds. 4. Treatment of industrial effluents done in three phases: a. Primary treatment by mechanical means. This involves screening, grinding, flocculation and sedimentation. b. Secondary treatment by biological process. c. Tertiary treatment by biological, chemical and physical processes. This involves recycling of wastewater. 5. Overdrawing of ground water reserves by industry where there is a threat of ground water resources also needs to be regulated legally.
Minimizing air pollution: 1. Particulate matter in the air can be reduced by fitting smoke stacks to factories with electrostatic precipitators, fabric filters, scrubbers and inertial separators. 2. Smoke can be reduced by using oil or gas instead of coal in factories.
Minimizing noise pollution: 1. Machinery and equipment can be used and generators should be fitted with silencers. 2. Almost all machineries can be redesigned to increase energy efficiency and reduce noise. 3. Noise absorbing materials may be used apart from personal use of earplugs and earphones.