The Class 9 is an important year in a student’s life and Maharashtra State Board Science is one of the subjects that require dedication, hard work, and practice. It’s a subject where you can score well if you are well-versed with the concepts, remember the important formulas and solving methods, and have done an ample amount of practice. Worry not! Home Revise is here to make your Class 9 journey even easier. It’s essential for students to have the right study material and notes to prepare for their board examinations, and through Home Revise, you can cover all the fundamental topics in the subject and the complete Maharashtra State Board Class 9 Science Book syllabus.
1. Match the words given in column ‘A’ with the correct ones from column ‘B’ to explain their impact on the environment.
| Column A | Column B |
| Harmful Waste | Glass, rubber, carry bags, etc. |
| Domestic waste | Chemicals, pigments, ash, etc. |
| Biomedical waste | Radioactive Material |
| Industrial waste | Left over food, vegetables, peelings of fruits |
| Urban waste | Bandages, cotton, needles, etc. |
Answer:
| Column A | Column B | Impact On Environment |
| Harmful Waste | Radioactive Material | Not just contaminates the environment, but also affects the health |
| Domestic waste | Left over food, vegetables, peelings of fruits | Reason for bad smell and spread of diseases |
| Biomedical waste | Bandages, cotton, needles, etc. | Could be instrumental in spreading diseases |
| Industrial waste | Chemicals, pigments, ash, etc. | Releases poisonous gases |
| Urban waste | Glass, rubber, carry bags, etc | Collecting these could cause calamity |
2. How is first aid provided to victims of disasters who are injured?
Answer: Given below are the basic principles of the first aid provided to the victims of disaster who are injured:
Life and Resuscitation –ABC
1) If the victim is finding it difficult to breathe, keep their head in a sloping position and the chin raised, thus leaving the respiratory passage open
2) Give mouth to mouth resuscitation for the victim if their breathing has stopped
3) In case the victim is unconscious, even after giving the mouth to mouth respiration, two times, then press down the heart hard by pressing the chest with both palms. Alternate these actions every fifteen minutes. This process is known as Cardio Pulmonary Resuscitation (CPR). This brings back the blood circulation to normal.
4) In case the victim had been bleeding, apply an antiseptic on the wound, press down an antiseptic pad and apply pressure for 5 minutes using either the thumb or the palm
5) In case of any fracture, the fractured area will be immobilised with the help of wooden rods/batons/rulers. In case of an impact on the back or vertebral column, the victim should remain immobile on a firm stretcher.
6) Hold the injured part under the clean and cold water for ten minutes in case of any burns
7) Finally, if the victim has a sprain or have twisted their leg, then the RICE remedy should be considered. The victim should first sit in a relaxed position, then an ice-pack has to be applied on the injured part and then the injured part has to be massaged thoroughly. Be sure to keep the injured part in an elevated position.
3. State the scientific and eco-friendly methods of waste management
Answer: It is the need of the hour to adopt solid waste management practices so as to avoid the possible problems arising due to solid waste that are produced from the urban and industrial areas and also to maintain a clean environment. Bio-medical waste management (Incineration), composting, safe landfill sites, vermi-composting, Industrial solid waste management (land-fill method) and Pyrolysis (energy production by burning of waste at high temperature Ex. Biogas, Bioelectricity) are some scientific and eco-friendly methods of waste management.
4. Explain with suitable examples, the relationship between weather forecasting and disaster management.
Answer: If present climatic conditions are analysed with reference to the past climatic conditions, then we can predict climatic changes of the future. Forecasting is all about predicting how the weather is going to be, whereas disaster management means to take the necessary precautions prior to the occurrence of disasters such as earthquakes, floods and so on. It is known that disasters take place as a result of the disturbance in the biosphere or the ecosystem. Hence, if a weather forecast predicts impending bad weather that could result in a disaster, with the help of disaster management people will be better equipped to face the weather. Take for example, that weather forecast is predicting very heavy rain, then people would be ready for the incident of a flood with the help of disaster management.
5. Why is e-waste harmful? Express your opinion about this.
Answer: E-waste is the electronic waste such as discarded old electronic appliances that include computers, TVs, refrigerators, cell phones, batteries and so on. Though earlier, much of the e-waste was manufactured in cities, currently, even smaller towns and villages are contributing to it. Meanwhile, e-wastes are harmful and polluting. It consists of dangerous products like lead, mercury, plastics and more, which are not just non-biodegradable but are also the cause for many life threatening diseases like Cancer. Throwing away e-waste to water is also a threat to sea-life.
6. Write notes on Meteorology.
Answer: Meteorology involves studying the inter-relationship between several parts of air, natural cycles, geological movements of the earth and the climate. It deals with the study of clouds, thunder, lightning, storms, rainfalls and more. Now, based on the study of these factors, weather forecasting is done, which is found to be useful for farmers, water transport, common people, fisheries, aviation services and several other organizations. The tradition of forecasting the monsoon season in India is older than 100 years. Several models are used for weather forecasts. Let’s begin with:
Mathematical Model (Dynamic) – Forecasts that are done via mathematical models take into account the current weather related events and the ongoing physical interactions between them. Param supercomputers help to mathematically analyse data about the current climatic parameters with the help of the Various mathematical models based upon daily geographic events.
Holistic model- In this, the predictions are based on these parameters used in other models that have the greatest effect on the monsoon. Nowadays, predictions declared by IMD are the collective outcome of several models. This is called a holistic model.
Statistical model -Here, the present climatic observation in a region is compared with earlier parameters like atmospheric pressure, the nature of monsoon rainfall of several years and oceanic temperature. Statistical methods are employed to analyse the data and even predictions are made about the monsoon in the present conditions.
7. State the seven principles of solid waste management.
Answer: Given below are the principles of solid waste management:
1)Reuse -some of the materials can be reused for other purposes
2)Refuse –do not use non-degradable items such as plastic, thermocol etc,
3)Recycle -recycle solid wastes such as paper, glass and so on
4)Rethink -rethink the use of several items as well our activities
5)Reduce- limit the consumption of resources in order to avoid wastage and reuse old materials as well as share things. Avoid using discardable items.
6)Research -research on the reuse of materials, which are out of use, temporarily
7)Regulation and public awareness- Adhere to the rules and regulations of waste management and encourage others to do the same.
8. Explain the difference between degradable and non-degradable waste.
Answer: Biodegradable wastes are broken down into smaller components by the living organisms. Breakdown of these wastes enriches the soil with plant and animal waste, which are good for the soil. Meanwhile, it is not possible to break down non-degradable waste into simple substances using living organisms. Non-biodegradable wastes also cause soil pollution, which is harmful for the soil.
9. What is the weather and climate?
Answer: Weather is the atmospheric conditions at a specific time at a particular place, whereas the average daily readings of various weather-related parameters recorded for several years is known as the climate. Climate is a predominant condition of the atmosphere, which is long-term.
10. Name the weather related climatic factors.
Answer: Some of the weather related climatic conditions are given here. They are atmospheric pressure, sunlight, clouds, humidity, rainfall, visibility, temperature and such.
11. What is the important role of climate in our day to day life?
Answer: Climate has a crucial role to play in our day to day life, influencing our basic needs such as food, clothing and shelter as well as our occupations. It is especially significant for an agrarian country such as India. Meanwhile, the climatic factors such as temperature, the speed and direction of wind, atmospheric pressure and so on influence the construction of runways, seaports, huge bridges and skyscrapers, etc.
12. Which day is observed as ‘World Meteorological Day’?
Answer : 23 March is celebrated as ‘World Meteorological Day.’.
13. What is the importance of weather in the living world?
Answer: It is evident that the study of meteorology or the climate is very important from the view of human life. Given here are a few points:
14. What are observatories?
Answer: During the process of determining the climate of a specific region, a review of the earlier studies about the several aspects of the climate is considered as crucial. A large number of countries across the world have set up meteorology departments to make these observations and to record them. These departments have ‘observatories’ equipped with modern instruments and technology.
15. What is the main role of the World Meteorological Organization?
Answer: The World Meteorological Organization, set up on 23 March 1950 by the United Nations Organization has a crucial role to play in food security, water management, transportation and communication.
16. Where are the offices of Indian Meteorological Societies located?
Answer : The India Meteorological Department established in 1875 by the British in Shimla has its head office in Pune as well as regional offices across Mumbai, Kolkata, Chennai, Nagpur and Delhi.
17. What are the functions of The India Meteorological Department?
Answer: Information about weather and climatic conditions are imparted to other departments such as shipping, marine oil exploration, aviation, agriculture, production, irrigation and so on by the India Meteorological department. It also communicates to other departments, citizens and mass communication media to further predictions about calamities, including sand storms, hot and cold waves, dust storms, tsunami, heavy rainfall etc. To do so, India has also introduced various satellites of high class technology. Meanwhile, observatories are also established at various locations for doing excellent work in the analysis of the information received from these satellites.
18. Write about Monsoon model and climate prediction.
Answer: As old as 100 years, the tradition of monsoon forecasting had been prevalent for so long. It was in 1877, following the famine that H.F. Blanford, the originator of IMD made the first prediction about monsoon considering the snowfall in the Himalayas as the parameter. Also, in the 1930 ’s, Sir Gilbert Walker, the Director of IMD emphasized on the relationship between several global climatic factors and the Indian monsoon. On the basis of the observations and previous recordings related to this relationship, he also put forward an hypothesis about the nature of the monsoon. Finally, in the 1990s, a monsoon model as per the global climatic parameters was produced under the initiative of Dr. Vasantrao Govarikar, which was utilised from 1990 to 2002.
19. Why do meteorological models need to be changed continually?
Answer: Every meteorological model is dependent upon the inter-relationship that exists between the parameters in the model and the results expected from it. Nevertheless, because the reference to the ocean and the atmosphere do not remain constant, the meteorological models have to be changed continuously.
20. What is solid waste?
Answer: Solid waste is the waste materials that are released via the several daily human activities. They are a good source of energy if disposed of properly. In today’s scenario, solid waste is a main problem, as it could result in both soil and water pollution. It is also an issue from the standpoint of economic development, environmental degradation as well as health.
21. What is the Solid waste generated in the main metro cities?
Answer: 5000 tons in Mumbai, 1700 tons in Pune and 900 tons in Nagpur are the approximate amount of solid waste that is generated in the main metro cities of Maharashtra.
22. What caused the 26 July 2005 flood calamity in Mumbai?
Answer: A serious flood calamity occurred on 26 July 2005 in Mumbai. Improper solid waste management was one of the chief causes of that calamity.
23. What is the source of mining waste?
Answer: Some of the chief sources of mining waste include the remains of heavy metals such as lead, arsenic, cadmium and so on, which are extracted from mines.
24. What is called “wet solid waste” or “wet garbage” ?
Answer: Waste such as the kitchen waste (spoiled food, fruits, vegetables), soil, ash, dung, plant parts and so on that are easily degraded by microbes are the biodegradable waste also known as “wet solid waste” or “wet garbage”. Compost and fuel of good quality can be extracted from it, if it is carefully decomposed.
25. What is “dry waste” or “dry garbage”?
Answer: Not that easily degradable, the dry waste or dry garbage makes use of a long period of time and various techniques. Plastic, metals and other materials are examples of non-biodegradable waste.
26. What are the main harmful effects of solid waste?
Answer: Given below are some points to show the harmful effects of solid waste:
1)Adversely affect biodiversity
2)Generates bad odour of waste
3)Produces poisonous gases
4)Result in Degradation of natural beauty
5)Cause air and water pollution
6) Result in soil pollution
7)Lead to spreading diseases
27. Why is solid waste management the need of the hour?
Answer: Given here are some of the benefits of solid waste management:
1.Helps to prevent environmental pollution and to clean the surroundings
2. Energy and Fertilizer production is on the rise and via it produces more work and employment opportunities
3. Decreases the strain on natural resources via treatment of solid waste
4. Boosts the health and quality of life and maintains environmental balance.
28. What is the 3R Mantra of waste management?
Answer: The 3 R Mantra is Reduce (reducing the waste), Reuse (reuse of waste) and
Recycle (recycling of waste).
29. Who is the largest producer of electricity from solid waste?
Answer: America is the largest producer of electricity from solid waste.
30. What is the Period of Natural Degradation for the following products?
Answer: The period of natural degradation for products varies. Here, we have mentioned a few:
a)Banana Peelings will last for 3 to 4 weeks
b)Cloth bags can last a month
c)Wood may degrade in 10 to 15 years
d) Thermocouple / Styrofoam cups have infinite duration
e) Period of natural degradation of certain plastic bags is 10 lakh years
31. Which disasters have caused large scale damage to life and property?
Answer: Several natural disasters such as thunder and lightning, floods, fire as well as man-made disasters, including accidents, bomb explosions, chemical accidents in industries, stampedes in mass gatherings, riots and more have caused large scale damage to life and property.
32. Write about disaster management.
Answer : An action implemented via proper planning, organized activity and coordination, disaster management consists of prevention of loss and danger, boosting tolerance, providing relief from disaster by minimising the intensity and the extent of harm, preparation to face the disaster, immediate action in the disaster situation, thorough assessment of damages and the intensity of the disaster, organising the rescue work and help, rehabilitation and rebuilding and so on.
33. How to transport victims / patients?
Answer: There are several methods used to carry a patient. They are:
34. What are the other emergency measures adopted during disasters?
Answers: Civil administration makes use of boats to rescue people who are trapped in a flooded area. Other items like wooden boards, bamboo floats and air filled rubber tube from a tyre are used to advantage, as an emergency measure. Fire extinguishers, a portable appliance can also be used to put out a fire.