Science and Technology Class 9 Question Answers Chapter 9 Maharashtra Board

Environmental Management

1. Match the items in column ‘A’ with the proper ones in coloum ‘B’ and explain their impact on the environment.

Column ‘A’                   Column ‘B’
1. Harmful waste – a. Glass, rubber, carry bags, etc.
2. Domestic waste – b. Chemicals, pigments, ash, etc.
3. Biomedical waste – c. Radioactive material
4. Industrial waste – d. Left over food, vegetables, peelings of fruits.
5. Urban waste – e. Bandages, cotton, needles, etc.

Answer:

(1 – c),
(2 – d),
(3 – e),
(4 – b),
(5 – a)

2. Complete the statements using the given options and justify those statements.

(Geographic favourability, climate, weather, observatory)

a. Of the abiotic factors that affect biodiversity by far the most important is ……………… .

Answer: Climate.

Climate influences our basic needs like food, clothing and shelter as well as our occupations. Various factors of climate like temperature, atmospheric pressure, sunlight, rainfall, humidity etc. will decide which kind of plants and animals can survive there.

b. A description of the climatic conditions of short duration in a particular area is ……………… .

Answer: Weather.

Atmospheric conditions at a specific time at a particular place are referred to as weather. Weather is related to a specific location and specific time whereas climate is related to a longer duration and larger area.

c. Irrespective of the progress of human beings, we have to think about ……………… .

Answer: Geographical favourability.

Geographical favourability includes location, availability of water, availability of natural resources and climate of a region. This has a great impact on the progress of human beings. Countries that have more favourable factors will progress more.

d. Establishments where various climatic factors are recorded are called ……………… .

Answer: Observatories

Most countries in the world have established meteorology departments for recording climatic factors. These departments have observatories which are equipped with modern instruments and technology.

3. Answer the following questions.

a. How is first aid provided to victims of disasters who are injured?

Answer:

1. Bleeding: If the victim is injured and bleeding through the wound, the wound should be covered with an antiseptic pad and pressure applied on it for 5 minutes with either thumb or palm.

2. Fracture and impact on vertebrae: If any bone is fractured, it is essential that the fractured part be immobilized. It can be done with the help of any available wooden rods / batons / rulers. If there is an impact on the back or vertebral column; the patient should be kept immobile on a firm stretcher.

3. Bums: If victims have bum injuries, it is beneficial to hold the injured part under clean and cold flowing water for at least 10 minutes. How is Solid Waste classified? OR What are the sources of Solid Waste?

4. Domestic waste: Waste food, paper, plastic paper, plastic bags, vegetable waste, fruit skins, glass and sheet metal articles, etc.

5. Industrial waste: Chemicals, pigments, sludge, ash, metals, etc.

6. Hazardous waste: Chemicals generated in various industries, radioactive materials, explosives, infectious materials, etc. Farm/Garden 7. waste: Leaves, flowers, branches of trees, crop residues like straw, animal urine and dung, pesticides, remains of various chemicals and fertilizers, etc.

8. Electronic waste: Non-functional TV sets, cell phones, music systems, computers and their parts, etc.

9. Biomedical waste: Bandages, dressings, gloves, needles, saline bottles, medicines, medicine bottles, test tubes, body parts, blood, etc. from clinics, hospitals, blood banks and laboratories. Urban waste: Waste generated through household industries and large commercial and industrial establishments, carry bags, glass, metal pieces and rods, threads, rubber, paper, cans from shops, vegetable and meat markets, construction waste, etc.

10. Radioactive waste: Radioactive materials like Strontium-10, Cerium-141, Barium-140 and heavy water, etc. generated from atomic energy plants, uranium mines, atomic research centres, nuclear weapons testing sites, etc.

b. State the scientific and eco-friendly methods of waste management.

Answer:

Following are the scientific and eco-friendly methods of waste management:

• Waste separation: In this method, dry and wet wastes are separated, stored and later collected for proper use.
• Composting: Decomposition of degradable kitchen waste in small pits in the backyard, garden or terrace is called composting. Good quality manure can be produced by composting leftover food, peels of fruits, vegetables etc.
• Vermicomposting: Converting solid waste into manure or compost with the help of earthworms is called vermicomposting.
• Vermicompost manure is highly nutritious and can be used for agricultural purposes and garden plants.
• Secured landfill: Solid waste is disposed off in secured landfills.
• The site for secured landfill is selected minimum 2 km away from water bodies and human habitation.
• Care is taken to see that the site does not fall in sensitive zone.
• The landfills are layered with clay and plastic and then the garbage is spread and left to decompose naturally.
• Pyrolysis: In this method, the waste is heated to a high temperature to obtain gas and electricity.
• Semi-combustible waste is burnt in pyrolysis. It is suitable for municipal solid waste management.
• Incineration: Biomedical waste is burnt in incinerators to kill the pathogens. Disinfection and sterilization is also done while treating the biomedical waste.

c. Explain with suitable examples, the relationship between weather forecasting and disaster management.

Answer:

1. Depending upon the factors such as storms, clouds, rainfall, etc., weather forecasts are made. It is useful in aviation, shipping, fishing, industries as well as during natural calamities like dust storms, sand storms, heavy rainfall, tsunami etc where proper predictions are made with well equipped satellites and highclass technology.
2. Observatories at several locations are doing excellent work in the analysis of the information received from these satellites.
3. This data can be used in prevention of losses and danger, improving tolerance, providing relief from disaster, minimising the intensity and extent of harm as well as preparation to face the disaster.

d. Why is e-waste harmful? Express your opinion about this.

Answer:

• e-waste is electronic waste which includes non-functional TV Sets, cell phones, music systems, computers and their parts, etc.
• E-waste contains heavy metals like lead, beryllium, mercury and cadmium.
• These metals accumulate in the soil for long periods and thus affect the biodiversity of the soil.
• Many a times e-waste like battery etc. contain acids which make the soil acidic.
• e-waste can cause ground water pollution, which also affects living organisms when they drink this polluted water.
• Thus, e-waste affects human health and soil microorganisms directly or indirectly.

e. How will you register individual your participation in solid waste management?

Answer:

We can register our individual participation in solid waste management in the following ways:

• Following the 3R mantra: Reduce (reducing the waste), reuse (reuse of waste) and recycle (recycling of waste).
• Throwing plastic wrappers of chocolates, ice-creams, biscuits, etc. into dust bins. Avoid littering.
• Avoiding the use of plastic bags and instead using cloth bags or bags prepared from old sarees, bed-sheets, curtains, etc.
• Using both sides of a paper for writing. Reusing greeting cards and gift papers.
• Avoiding use of tissue paper and preferring to use one’s own handkerchief.
• Using rechargeable batteries instead of lead batteries.
• Implementing various programmes of solid waste management and educating, encouraging the family and society in this regard.

• Avoiding ‘use and throw’ type of articles like pens, canned cold drinks and tetra-packs etc.

4. Write notes.

Meteorology

• Meteorology is the science that studies weather, air components, and climate.
• It focuses on storms, clouds, rainfall, thunder, and lightning.
• Weather forecasts from meteorology help farmers, fishermen, aviation, and shipping plan activities.
• Example: Predicting rain helps farmers decide when to plant crops.

Climatic Factors

• These are elements like temperature, wind speed, humidity, atmospheric pressure, and rainfall.
• They decide the weather at a place and the climate over a long time.
• They affect our food, clothes, homes, and jobs.
• Example: High temperature in Rajasthan shapes the lifestyle of people there.

Monsoon Model

• A system to predict the monsoon season in India.
• Started by H. F. Blanford in 1877 using Himalayan snowfall.
• Improved by Sir Gilbert Walker in the 1930s with global weather factors.
• Dr. Vasantrao Govarikar’s 1990s model used 16 factors; now supercomputers like Param help make accurate predictions.

Industrial Waste

• Waste from factories, like chemicals, ash, metals, and sludge.
• It pollutes water, soil, and air, harming health and the environment.
• Proper disposal and recycling are needed to reduce its impact.
• Example: Factory chemicals can pollute rivers if not treated.

Plastic Waste

• Non-degradable waste like plastic bags, bottles, and packaging.
• Takes millions of years to break down, causing soil and water pollution.
• Recycling and reducing plastic use help manage it.
• Example: Plastic bags clog drains, leading to floods.

Principles of First Aid

• First aid prevents death, stabilizes health, and starts recovery during disasters.
• Airway: Clear breathing passage by tilting head back.
• Breathing: Give mouth-to-mouth resuscitation if breathing stops.
• Circulation: Use CPR (chest compression and breaths) for unconscious victims.
• Bleeding: Press antiseptic pad on wounds to stop bleeding.
• Fractures: Immobilize broken bones with rods; keep spine injuries still.
• Burns: Cool burns with cold water for 10 minutes.
• RICE: For sprains-Rest, Ice, Compression, Elevation.

5. Give examples of the importance of climate in the living world with explanations, in your own words.

Answer:

1. Daily weather as also long term climatic conditions influence human lifestyle directly or indirectly.
2. Land, water bodies, plants and animals collectively form the natural environment on earth. This environment is responsible for the development of organisms.
3. The climate of a particular region helps to determine the diet, clothing, housing, occupations and lifestyle of the people of that region. For example, the characteristic lifestyle of Kashmiri and Rajasthani people.
4. Salinity of marine water, formation of oceanic currents, water cycle, etc. are all related to various weather and climatic factors.
5. Various climatic factors bring about the weathering of rocks in the earth’s crust.

6. Explain with suitable examples, the care to be taken when using the methods of transporting patients.

Answer:

• Cradle Method: This method is used for children and under-weight victims.
• Carrying piggy back: This method is used for carrying patients who are unconscious.
• Human crutch method: If one of the legs is injured, the victim should be supported with minimum load on the other leg.

• Pulling or lifting method: This method is used for carrying an unconscious patient, through a short distance.
• Carrying on four-hand chair: This method is used when support is needed for the part below the waist.
• Carrying on two-hand chair: This method is useful for those patients who cannot use their hands but can hold their body upright.
• Stretcher: In an emergency, if a conventional stretcher is not available, then a temporary stretcher can be made using bamboo, blanket, etc.

7. Explain the differences.

a. Weather and climate

Answer:

b. Degradable and non-degradable waste.

Answer: